Lake Effect Snow Warning
See active warnings, advisories, and watches
For U.S. lake-effect regions
What Is Lake Effect Snow
Lake effect snow occurs when very cold, dry air moves over a warmer, unfrozen lake, such as one of the Great Lakes. The air takes in moisture and heat from the lake, then drops that moisture as snow once it reaches land. Because these snow bands are so narrow, one town might receive a significant amount of snow while a nearby area receives little or none.
Source of the Snow
Lake effect snow forms when cold air passes over warm lake water, making the air absorb moisture and heat.
Very Narrow Impact
This type of snow falls in narrow bands, often just 5 to 10 miles wide, instead of spreading across a whole state.
Wind Direction Matters
Even a slight change in wind direction can move the snow band to a different area.
Can be Disruptive
Sudden, heavy bursts of lake effect snow can quickly make it difficult to see and create hazardous travel conditions.
What the Lake Effect Snow Warning Tool Does
Use this tool to check active lake effect snow warnings, advisories, and watches across U.S. lake effect regions. Select your area or route to instantly see if conditions affect you, so you can decide whether to delay departure, pack extra gear, or make alternate travel plans to stay safe and prepared.
3 Ways to View Alerts
You can view alerts by state, by lake (such as Lake Erie or Lake Ontario), or by ZIP code for more accurate details.
Pulls Live NWS Data
The tool relies on the official National Weather Service feed, providing you with up-to-date warnings and advisories every five minutes. This timely information enhances trust and ensures you are always receiving the latest alerts.
Built for Winter Users
Parents, school administrators, drivers, and travelers can use this tool to stay informed about changing winter weather conditions.
When You Should Check This Tool
Use the lake effect snow warning tool when cold air moves over the Great Lakes or Great Salt Lake, or if winter forecasts suggest possible lake effect snow.
Before School or Work
See if current or upcoming weather could lead to closures or delays. To find out your area’s snow day chances, try the Snow Day Calculator, your go-to tool for predicting school and work closures this winter.
Before a Road Trip
Check if lake effect snow could make part of your route dangerous while other areas remain clear. Before heading out on a road trip, use the Wind Chill Calculator to anticipate how cold it might feel and plan your clothing and essentials accordingly.
During Active Snow Bands
When snow bands are active, refresh the tool to see the latest alerts.
Safety & Reliability
This tool displays official National Weather Service alerts in a simplified format. Always follow local authorities and emergency instructions for real-time updates.
Which States Are Supported
The tool is designed for states that frequently experience lake effect snow. If you enter a ZIP code outside these areas, you’ll get a friendly message and can check which states are supported below.
Currently Covered
The supported states are Michigan, Wisconsin, New York, Pennsylvania, Ohio, Indiana, Illinois, Minnesota, and Utah.
Why Just These
These states are located downwind of the Great Lakes or the Great Salt Lake, where lake effect snow often forms.
If Your ZIP isn’t Supported
You can still see alerts by choosing the “By State” option to pick a supported state or the “By Lake” option to focus on a specific lake area.
Frequently Asked Questions
These are the most common questions about the Lake Effect Snow Warning Tool and how it can help you stay informed, prepared, and safe during winter weather.