Weather Terms

Understanding weather terms, including the distinction between a watch and a warning, empowers individuals and communities to make informed decisions, take timely action, and reduce the potential harm caused by severe weather events. It plays a critical role in enhancing public safety and preparedness.

Severe Weather


  • Flood watch: issued when flooding is possible.
  • Flash flood watch: issued when flash flooding is possible. Be prepared to move to higher ground.
  • Flood warning: issued when flooding is occurring or will occur soon; if advised to evacuate, do so immediately.
  • Flash flood warning: issued when a flash flood is occurring; seek higher ground on foot immediately.


  • Tornado watch: Issued when a tornado is possible in your area.
  • Tornado warning: issued when a tornado has been sighted or indicated by weather radio.



EF0, EF1

Wind speeds of 65 to 110 mph


EF2, EF3

Wind speeds of 111 to 165 mph


EF4, EF5

Wind speeds of 166 to 200 mph or more



  • Winter storm watch: indicates that severe winter weather may affect your area.
  • Winter storm warning: indicates that a winter storm is occurring, or will occur, in your area. 
  • Wind chill: Calculations of how cold it feels outside when the effects of temperature and wind speed are combined. 
  • Frost/freeze warning: when below-freezing temperatures are expected.
  • 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.
  • Ice storm: when damaging accumulations of ice are expected during freezing rain situations. 


  • Tropical depression: a rotary circulation of clouds with winds up to 38 mph.
  • Tropical storm: a rotary circulation with winds between 39 mph and 73 mph.
  • Hurricane watch: issued when hurricane conditions are possible within 48 hours or less.
  • Hurricane warning: issued when hurricane conditions are expected in 36 hours or less.
  • Storm surge: a huge dome of water pushed on shore by a hurricane.


A hurricane's strength is normally described as being in one of five categories. These categories have been extracted from the SAFFIR-SIMPSON Hurricane Scale and are listed below, along with the wind strengths and potential damage to be experienced.


Sustained winds



Winds 74 to 95 miles per hour (mph)

Damage primarily to shrubbery, tree foliage, poorly constructed items, and unanchored mobile homes.

Storm Surges 4' to 5' above normal tide levels.

Low lying coastal roads inundated, minor pier damage, and some small craft torn from moorings in exposed anchorage.


Winds 96 to 110 mph

Some trees blown down.

Major damage to poorly constructed items and some damage to other structures (such as roofing material).

Storm Surge of 6' to 8' above normal tide levels.

Considerable damage to piers and marinas flooded.

Evacuation of some shoreline residences and low-lying areas required.


Winds 111 to 130 mph

Foliage torn from trees and large trees blown down.

Poorly constructed items destroyed, damage to roofing materials windows, and doors expected.

Mobile homes destroyed and some structural damage to small buildings.

Storm Surge 9' to 12' above normal tide levels.

Serious flooding at coast and small structures located there destroyed.

Larger structures near coast damaged by battering waves and floating debris.

Major erosion to beaches and massive evacuation of all residences within 500 yards of beach and single-story residences on low ground within 2 miles of shore.


Winds 131 to 155 mph

Shrubs, trees, and signs blown down. Extensive damage to roofing materials, windows and doors.

Complete failure of roofs on many small residences.

Storm Surge 13' to 17' above normal tide levels.

Flat terrain 2 feet or less above sea level flooded up to 6 miles inland.

Major damage to lower floors of structures near shore due to flooding and battering of waves and debris.


Winds greater than 155 mph

Damage as above plus complete failure of roofs on may residential and industrial buildings.

Extensive shattering of window and door glass.

Many complete building failures and small buildings overturned or blown away.

Storm Surge grater than 18' above normal tidal levels.

Massive evacuation of residential areas on low grounds within 5 to 10 miles of shore possibly required.