SHERIFF'S CORNER: Weather Alerts and Storm Advisories

Sheriff Rich Martin

Sheriff Rich Martin

Courtesy of Rich Martin, Lake County Sheriff's Office

Well, Winter has arrived or at least for the moment. With the recent winter storm, I thought it would be a good idea to go over what storm advisories mean and what necessary precautions should be considered when a weather alert has been issued.

In this edition of the "Sheriff's Corner", I talk about storm warnings, watches, advisories as well as other weather definitions and notifications. 


Calls for the creation of a government weather bureau began as early as 1844. In 1870, the Weather Bureau of the United States was established with a mission to "provide for taking meteorological observations at the military stations in the interior of the continent and at other points in the States and Territories".

The Weather Bureau first became a civilian enterprise in 1890, when it became part of the Department of Agriculture. The Bureau would later be moved to the Department of Commerce in 1940. In 1957, the Bureau began using radars for short-term forecasting of local storms and hydrological events.

The Bureau then became part of the Environmental Science Services Administration when that agency was formed in 1966. The Environmental Science Services Administration was renamed the National Oceanic and Atmospheric Administration in 1970, with the enactment of the National Environmental Policy Act. At this time, the Weather Bureau became the National Weather Service.

The National Weather Service is the current agency that is tasked with providing weather forecasts, warnings of hazardous weather, and other weather-related products to organizations and the public for the purposes of protection, safety, and general information.

The National Weather Service is divided into 122 local branches, known as Weather Forecast Offices, to issue products specific to those areas. Each WFO maintains a specific area of responsibility spanning multiple counties, parishes or other jurisdictions within the Continental United States – which, in some areas, cover multiple states – or individual possessions.


So, let's get into the specific definitions of each weather alert and the criteria needed for a particular alert to get issued.

*Advisory – An advisory is issued when a hazardous weather or hydrologic event is occurring, imminent, or likely. Advisories are for less serious conditions than warnings, that cause significant inconvenience and if caution is not exercised, could lead to situations that may threaten life or property.

*Watch – A watch is used when the risk of a hazardous weather or hydrologic event has increased significantly, but its occurrence, location or timing is still uncertain. It is intended to provide enough lead time so those who need to set their safety plans in motion can do so in advance if a forecasted event should occur. A watch means that hazardous weather is possible, but not imminent. People should have a plan of action in case a storm threatens and monitor various avenues that provide NOAA-disseminated data to listen for later information and possible warnings, especially when planning travel or outdoor activities.

*Warning – A warning is issued when a hazardous weather or hydrologic event is occurring, imminent or likely. A warning means weather conditions pose a threat to life or property. People in the path of the storm need to take protective action.

*Special Weather Statement (or Significant Weather Advisory) – A special weather statement is issued when something rare or unusual is occurring. These are usually triggered by sudden changes in meteorological conditions.


*Winter Weather Advisories are issued when snow, blowing snow, ice, sleet, or a combination of these wintry elements is expected but conditions should not be hazardous enough to meet warning criteria. Be prepared for winter driving conditions and possible travel difficulties. Use caution when driving.

*Wind Chill Advisories are issued when low wind chill temperatures are expected but will not reach local warning criteria. Extremely cold air and strong winds will combine to generate low wind chill readings. If you must venture outdoors, take precautions against frostbite and hypothermia. 

*Lake Effect Snow Advisories are issued for widespread or localized lake effect snowfall accumulation (and blowing snow) remaining below warning criteria. Expect lake effect snow showers and assume travel will be difficult in some areas. Some localized snow bands will be intense enough to produce several inches in a few areas with sudden restrictions in visibility.


*Winter Storm Watches are issued when conditions are favorable for a significant winter storm event (heavy sleet, heavy snow, ice storm, heavy snow and blowing snow or a combination of events).

*Wind Chill Watches are issued when there is the potential for a combination of extremely cold air and strong winds to create dangerously low wind chill values. 


*Blizzard Warnings are issued for frequent gusts greater than or equal to 35 mph accompanied by falling and/or blowing snow, frequently reducing visibility to less than ¼ mile for three hours or more. A Blizzard Warning means severe winter weather conditions are expected or occurring. Falling and blowing snow with strong winds and poor visibility are likely, leading to whiteout conditions making travel extremely difficult. Do not travel. If you must travel, have a winter survival kit with you. If you get stranded, stay with your vehicle and wait for help to arrive.

*Winter Storm Warnings are issued for a significant winter weather event including snow, ice, sleet or blowing snow or a combination of these hazards. Travel will become difficult or impossible in some situations. Delay your travel plans until conditions improve.
Ice Storm Warnings are usually issued for ice accumulation of around 1/4 inch or more. This amount of ice accumulation will make travel dangerous or impossible and likely lead to snapped power lines and falling tree branches. Travel is strongly discouraged.

*Wind Chill Warnings are issued for a combination of very cold air and strong winds that will create dangerously low wind chill values. This level of wind chill will result in frostbite and lead to hypothermia if precautions are not taken. Avoid going outdoors and wear warm protective clothing if you must venture outside. 

*Lake Effect Snow Warnings are issued when widespread or localized lake induced snow squalls or heavy showers are expected to produce significant snowfall accumulation. Lake effect snow usually develops in narrow bands and impacts a limited area. These bands can produce very heavy snow with sudden restrictions in visibility. Driving conditions may become hazardous at times.

*Ice Storm Warnings are issued when heavy ice accumulations that may cause significant disruptions to travel and public utilities, and damage to trees and utility infrastructure impacting life and property are imminent. Accumulations range from 1⁄4 to 1⁄2 inch or more of freezing rain on elevated horizontal flat surfaces.

*Snow Squall Warnings are issued when an intense, generally limited duration, period of moderate to heavy snowfall has been observed by radar. Usually accompanied by strong, gusty surface winds, significantly reduced visibility up to 1⁄4 mile or less (which may reach levels creating whiteout conditions), and possibly lightning; temperature drops behind an arctic front that are sufficient to produce flash freezes, in conjunction with a significant reduction in visibility from falling and/or blowing snow, may also serve as a warning criteria factor. Snow accumulation may be significant.


*Freezing Rain: Rain that freezes when it hits the ground; creating a coating of ice on roads, walkways, trees and power lines.

*Sleet: Rain that turns to ice pellets before reaching the ground. Sleet also causes moisture on roads to freeze and become slippery.

*Wind Chill: A measure of how cold people feel due to the combined effect of wind and cold temperatures; the Wind Chill Index is based on the rate of heat loss from exposed skin. Both cold temperatures and wind remove heat from the body; as the wind speed increases during cold conditions, a body loses heat more quickly. Eventually, the internal body temperature also falls and hypothermia can develop. Animals also feel the effects of wind chill; but inanimate objects, such as vehicles and buildings, do not. They will only cool to the actual air temperature, although much faster during windy conditions.


*Freeze Watch: A Freeze Watch is issued when there is a potential for significant, widespread freezing temperatures within the next 24-36 hours.

*Freeze Warning: A Freeze Warning is issued when significant, widespread freezing temperatures are expected. 

*Frost Advisory: A Frost Advisory is issued when the minimum temperature is forecast to be 33 to 36 degrees on clear and calm nights during the growing season. 

NOTE: These are all issued in the autumn until the end of the growing season (marked by the occurrence of the first widespread freeze). The normal end of the growing season is mid to late October, however, during anomalously warm autumns, the growing season may be extended past the normal end of the growing season. These warnings can also be issued in the spring at the start of the growing season (when it is late enough to cause damage to new plants and crops).


*A Severe Thunderstorm Watch is issued when severe thunderstorms are possible in and near the watch area. It does not mean that they will occur. It only means they are possible. Severe thunderstorms are defined as follows:
      1) Winds of 58 mph or higher;
      2) Hail 1 inch in diameter or larger.

*A Severe Thunderstorm Warning is issued when severe thunderstorms are occurring or imminent in the warning area. Severe thunderstorms are defined as follows:
      1) Winds of 58 mph or higher;
      2) Hail 1 inch in diameter or larger.

*A Tornado Watch is issued when severe thunderstorms and tornadoes are possible in and near the watch area. It does not mean that they will occur. It only means they are possible. Severe thunderstorms are defined as follows:
      1) Winds of 58 mph or higher
      2) Hail 1 inch in diameter or larger.
*A Tornado Warning is issued when a tornado is imminent. When a tornado warning is issued, seek safe shelter immediately.


*A Wind Chill Advisory is issued when wind chills are from -5F to -19F.

*A Wind Chill Warning is issued when wind chills are -20F or lower.

*A Dense Fog Advisory is issued when widespread fog is expected to reduce visibility to 1/4 mile or less over a large area for an extended period of time (2 or more hours).

*A High Wind Watch is issued when the following conditions are possible:
      1) sustained winds of 40 mph or higher for one hour or more;
      2) wind gusts of 58 mph or higher for any duration.

*A High Wind Warning is issued when the following conditions are expected:
      1) sustained winds of 40 mph or higher for one hour or more;
      2) wind gusts of 58 mph or higher for any duration.


We never want to forget our partners when it comes to public safety and the ability to prepare for weather emergencies. All of us want to thank those who work collectively with the Lake County Sheriff's Office on keeping the community safe during these critical times. The Lake County Road Commission, Lake County Central Dispatch, Lake County Emergency Management, area fire departments, Life EMS, Michigan State Police, Michigan Department of Natural Resources, U.S. Forestry Service, township and village governments, the Red Cross, Yates Dial-A-Ride, area churches, AA Collision & Towing, and Chetz Towing. None of this could be done if we did not have these professional and trained partners. All of us at the Lake County Sheriff's Office want to give a BIG THANKS to each and every one of you. Working together as a unified team, we can make a difference while providing a safe and enjoyable experience to those who live, work and visit Lake County.

This information is provided to you for clarification on specific laws, and not legal advice. This is not to be construed as a personal opinion, agreement or disagreement of any specific law. Topics covered are for educational and informational purposes only. As needed, excerpts from other articles are used for reference and/or content. If you have any questions on any specific topic, you may always email me your questions to