Different Weather Terms:
Weather terms and their definitions are from the National Weather Service.
Lake Effect Warning:
Widespread or localized lake effect snow that produces 7 inches of lake effect snow in 12 hours or 9 inches of lake effect snow in 24 hours.
Winter Weather advisory:
A Winter Weather Advisory will be issued for any amount of freezing rain, or when 4 to 6 inches of snow (alone or in combination with sleet and freezing rain), is expected to cause a significant inconvenience, but not serious enough to warrant a warning.
Winter Storm Watch:
A Winter Storm Watch is issued when there is the potential for significant and hazardous winter weather as the National Weather Service sees fit. It does not mean that significant and hazardous winter weather like a blizzard, heavy snow, heavy freezing rain, or heavy sleet will occur it only means it is possible.
Significant and hazardous winter weather is defined as a combination of:
1. 7 inches or more of snow/sleet AND/OR
2. 1/2 inch of ice accumulation or more to cause damage to trees or powerlines. AND/OR
3. A life threatening or damaging combination of snow and/or ice accumulation with wind.
Winter Storm Warning:
A Winter Storm Warning is issued when a significant combination of hazardous winter weather is occurring or imminent.
Significant and hazardous winter weather is defined as a combination of:
1. 7 inches or more of snow/sleet AND/OR
2. 1/2 inch of ice accumulation or more to cause damage to trees or powerlines. AND/OR
3. A life threatening or damaging combination of snow and/or ice accumulation with wind.
Snow Squall Warning:
A Snow Squall Warning is issued for the expectation of a short-lived but intense burst of snow, often accompanied by strong winds, that can drastically reduce visibility and cause flash freezes on roads.
Blizzard Warning:
A Blizzard Warning means that the following conditions are imminent or expected.
1. Snow and/or blowing snow reducing visibility to 1/4 mile or less for 3 hours or longer AND
2. Sustained winds of 35 mph or greater or frequent gusts to 35 mph or greater.
There is no temperature requirement that must be met to achieve blizzard conditions.
Ice Storm Warning:
1/2 inch or more of ice accumulation.
Frost Advisory:
A Frost Advisory is issued when the minimum temperature is forecast to be 32 to 37 degrees on clear and calm nights during the growing season. A Frost Advisory is issued in the autumn until the end of the growing season (marked by the occurrence of first widespread freeze). A Frost Advisory is issued in the spring at the start of the growing season (when it is late enough to cause damage to new plants and crops).
Freeze Watch:
A Freeze Watch is issued when there is a potential for significant, widespread freezing temperatures within the next 24-48 hours. A Freeze Watch is issued in the autumn until the end of the growing season (marked by the occurrence of first widespread freeze). A Freeze Watch is issued in the spring at the start of the growing season (when it is late enough to cause damage to new plants and crops).
Freeze Warning:
A Freeze Warning is issued when significant, widespread freezing temperatures below 32 degrees are expected. A Freeze Warning is issued in the autumn until the end of the growing season (marked by the occurrence of first widespread freeze). A Freeze Warning is issued in the spring at the start of the growing season (when it is late enough to cause damage to new plants and crops).
Cold Weather Advisory (Previously Wind Chill Advisory):
A Cold Weather Advisory is issued when the apparent temperature (feel like) is expected to fall to -15 to -24 degrees below zero.
Extreme Cold Warning (Previously Wind Chill Warning):
An Extreme Cold Warning is issued when the the apparent temperature (feel like) is expected to fall to or below -25 degrees.
Heat Advisory:
A Heat Advisory is issued when the heat index value is expected to reach 95 to 104 degrees
Excessive Heat Watch:
An Excessive Heat Watch is issued when there is a potential for the heat index value to reach or exceed 105 degrees within the next 24 to 48 hours. A Heat Advisory may be issued for lower criteria if it is early in the season or during a multi-day heat wave.
Excessive Heat Warning:
An Excessive Heat Warning is issued when the heat index value is expected to reach or exceed 105 degrees within the next 12 to 24 hours. An Excessive Heat Warning may be issued for lower criteria if it is early in the season or during a multi-day heat wave.
Flood Watch:
A Flood Watch is issued when conditions are favorable for flooding. It does not mean flooding will occur, but it is possible.
Flood Warning:
A Flood Warning is issued when flooding is imminent or occurring.
Flash Flood Warning:
A Flash Flood Warning is issued when flash flooding is imminent or occurring. There are three different tiers to this warning: Base, Considerable, Catastrophic.
Severe Thunderstorm Warning:
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 AND/OR
2. Hail 1 inch in diameter or larger.
Severe Thunderstorm Warning:
A Severe Thunderstorm Warning is issued when severe thunderstorms are occurring or imminent in the warning area. This warning is made up of three different tiers: Base, Considerable, and Destructive. Severe thunderstorms are defined as follows:
1. Winds of 58 mph or higher
2. Hail 1 inch in diameter or larger.
Tornado Watch:
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.
3. Tornado.
Tornado Warning:
A tornado Warning is issued when a tornado is imminent. When a tornado warning is issued, seek safe shelter immediately.
Wind Advisory:
A Wind Advisory is issued when the following conditions are expected:
1. Sustained winds of 31 to 39 mph for an hour or more. AND/OR
2. One or many wind gusts above 45 mph for any duration.
High Wind Watch:
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. One or many wind of 58 mph or higher for any duration.
High Wind Warning:
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. One or many wind gusts of 58 mph or higher for any duration.
Dense Fog Advisory:
A Dense Fog Advisory is issued when widespread fog is expected to reduce visibilities to 1/4 mile or less over a large area for an extended period of time (2 or more hours).
Air Quality Alert:
When levels of ozone and or fine particles are expected to exceed AQI value of 100 an Air Quality Alert is issued to alert sensitive groups to take caution.