Severe Weather Alert

Update: 3/26/2025 at 4:30pm

A Severe Thunderstorm Watch has been issued for our area from 3:15 - 9:00pm on Wednesday, March 26. 

Large hail is the primary hazard of concern, with hail of 1-2 inches in diameter possible. Heavy rain, lightning, and damaging winds with gusts of 58 mph and higher are also possible.

Remaining indoors is the best safety measure. To ensure the safety of the community and staff: 

• The Mercer Island School District has canceled all outdoor athletics and activities,
• City evening events have been canceled,
• The Mercer Island Community and Event Center will close at 5:30pm, and
• The Planning Commission Meeting has been canceled.

Residents should prepare for potentially damaging winds and hail and excessive rain. Preparations should include: 

• Bring in outdoor pets or move large animals into covered structures. 

• Park in a garage or covered area to protect your vehicle from hail damage. If no covered parking is available, cover your car with blankets, a car cover, floor mats, or towels to protect your windshield and rear windows and hood.

• Secure loose items on your property (umbrellas, garbage cans, etc.). Make sure storm drains as clear. 

• Stay informed. Monitor local news for updates.  

• Make sure the emergency alerts on your phone are turned on and that your phone volume is turned up. 

• Stay indoors during the storm. Lightning can travel up to 10 miles away. If you see lightning or hear thunder, get to shelter immediately and remain indoors for 30 minutes after the last clap of thunder. The shelter should be fully enclosed – not an open gazebo, picnic shelter, etc. 

• Be prepared for possible downed trees and power lines. 

• Prepare for power outages by charging cell phones, computers, back-up battery packs, and EVs. Fill gas tanks and replace batteries in flashlights and emergency radios that may be depleted after storms from earlier this season.

• Delay travel during the storm. Heavy rain and hail could reduce visibility and cause roadway ponding. Fill your gas tank and keep an emergency kit in the car.

• Check storm drains and areas of known poor drainage ahead of the storm. 

The National Weather Service (NWS) is forecasting thunderstorms tomorrow evening, Wednesday, March 26 . These storms, while expected to be brief and limited, could impact the evening commute.

The NWS is estimating a 30 – 50% chance of thunderstorms with a 15-30% chance for severe thunderstorms. There is also a very slight possibility that our region may see a tornado (2-4% chance). 

Severe thunderstorms could produce:

• Damaging hail, 1-2 inches in diameter
• Strong winds peaking at nearly 60 miles an hour
• Heavy rain
• Lightning
• The possibility of a tornado

How to prepare before and respond during the storm:

1. Secure loose items on your property (umbrellas, garbage cans, etc.). Make sure storm drains as clear.
2. Stay informed. Monitor local news for updates.
3. Make sure the emergency alerts on your phone are turned on and that your phone volume is turned up.
4. Stay indoors during the storm. Lightning can travel up to 10 miles away. If you see lightning or hear thunder, get to shelter immediately and remain indoors for 30 minutes after the last clap of thunder. The shelter should be fully enclosed – not an open gazebo, picnic shelter, etc..
5. Stay off the water. This isn’t the time to go swimming or boating.
6. Be prepared for possible downed trees and power lines.

If a tornado occurs, get indoors to the lowest level possible. Find a room with no windows, skylights, or glass doors. And just like we practice for earthquakes, get under something sturdy and protect your head. For more tips and information visit https://mil.wa.gov/tornado 

Get updates from the National Weather Service at www.weather.gov or www.facebook.com/NWSSeattle