Weather Defintions


Confused by meterological terms? Find out what they mean here.



Watch and Warning defenitions

Blizzard Warning- Issued when Significant blowing and drifting of snow with winds of 35 mph, and visibilities less than 1/4 mile.

Excessive Heat Warning- When Heat Indexs reach 115ºF or higher, or 80ºF low temperatures are expected.

Flash Flood Warning- After a period of very heavy rainfall, or a dam break will cause sudden flooding.

Flood Warning- Issued when for unusall ponding of water from rainfall, flash flooding is not expected.

Freeze Warning- issued when temperatures of 32ºF or colder are expected during the growing season.

Heavy Snow Warning- When 6 inches of snow or more is expected in 12 hours or less.

High Wind Warning- When non-thunderstorm winds are expected of 45mph for several hours, with gusts to 60mph.

Ice Storm Warning- Issued for expected accumulation of 1/4" or more of ice. This can bring down trees and power lines.

Severe Thunderstorm Warning- Issued when a Severe thunderstorm is imment or occuring. A severe thunderstorm contains 3/4" (penny-sized) hail, and/or winds of at least 58 mph. Frequent deadly cloud-to-ground lightning also occurs in most severe thunderstorms, but this alone does not mean a severe storm.

Tornado Warning- Issued when a Tornado is indicated on radar, or one is on the ground. Large hail, damaging winds, and lightning are also a threat. If a tornado warning is issued for your area, seek shelter in the lowest part of your home or busness, in an interior room, hallway, or closet. Use blankets and pillows to cover your body, always stay away from windows. Please see more details here.

Wind Chill Warning
- Issued for Wind chills expected to be below -35ºF.

Winter Storm Warning- Issued when a combination of dangerous winter weather conditons are expected. Example- 6 inches of snow, possibly mixing with sleet or freezing rain. Example- 4 inches of snow, mixing with sleet, and 1/4" of ice accumulation.

Flood Watch- Issued when widespread general flooding is likely. Often during widespread moderate to heavy rain events, such as tropical system remenace, or a a stalled front.

Severe Thunderstorm Watch- Issued for the possiblity of severe thunderstorms in a large area. Watches can cover around a dozen counties to entire states. Watches are in effect usually for 4-8 hours.

Tornado Watch- Issued for the possiblity of severe thunderstorms and tornadoes in a large area. Watches can cover around a dozen counties to entire states.  Watches are in effect usually for 4-8 hours. If a tornado watch is issued, plan ahead in case severe weather threatens your area.


Blowing Snow Advisory - A Blowing Snow Advisory means that blowing snow will reduce visibility 1/2 mile or less.

Dense Fog Advisory - Dense Fog Advisories may be issued for visibilities 1/4 mile or below, due to widespread fog.

Freezing Fog Advisory - A Freezing Fog Advisory will be issued when dense fog is present with temperatures below freezing, and the fog is expected to cause a thin layer of ice to develop on bridges, overpasses, and other elevated roadways.

Freezing Rain Advisory - Freezing rain is expected to fall, but accumlations will be less than 1/4". This will make roads slippery.

Heat Advisory- Heat Index expected to reach 105ºF, or nighttime low not below 80ºF.

Snow Advisory - A Snow Advisory means that 3-5 inches is expected to fall. 

Snow and Blowing Snow Advisory - A Snow and Blowing Snow Advisory is issued when 3-5 inches of snow is expected to fall AND blowing snow will make visibility 1/4 mile or less.

Urban and Small Stream Flood Advisory - An Urban and Small Streams Flood Advisories are issued when flooding of small streams, streets, and low-lying areas, such as railroad underpasses and urban storm drains, is occurring. 

Urban Flood Advisory - An Urban Flood Advisory is issued when flooding of streets, low lying areas or storm drains is either imminent or already occurring. 

Wind Advisory - Issued for sustained winds 35-40 MPH for a few hours or  gusts to 46-57 MPH.

Wind Chill Advisory - Issued when wind chills are expected to be between  -20 to -35ºF.

Winter Weather Advisory - A Winter Weather Advisory will be issued if conditions warranting two separate winter advisories are met.
































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