Hazardous Weather Outlook:
Definitions of Hazard Levels and Their Associated Triggers

Hazard Level
 0
 1
 2
 3
 4
 5
Threat to life or
property and/or
economic impact
 Nil
 Minimal
 Small
 Medium
 Significant
 Very
Significant
 





Grassland Fire Danger Index


Very High
 Extreme
 Ongoing Fires
Heat Index (0F)

100
 105 for 3 hours/
Advisory
 110 for 3 hours/
Warning
 110 for 3 hours/ Warning
for 3 days
Wind Chill (0F)

0
 -15 for 3 hours/
Advisory
 -25 for 3 hours/
Warning
 -25 for 3 hours/
Warning
for 3 days
Blowing Dust
or Smoke


  Blowing Dust Advisory
(3/8sm - 1sm)
 Blowing Dust Warning
< 3/8sm
Other Obstruction
to Visibility (statute miles)
 Nil
 Obstruction  to Visibility
in grids
 Patchy 1/2sm
 Advisory
 Widespread
<1/8sm
Wind
(non-convective)

Advisory High Wind Warning
 High Wind Warning
for 3 hours
or more
 Hurricane Force
Frost/Freeze Nil
 Frost
mentioned
Frost
Advisory
 Freeze
Warning

Lightning
 Nil
 Thunder mentioned



Hail
 Nil
 Below Significant
Weather Alert
 Significant Weather Alert
 Severe Hail Likely
 >= 2 inches
 > 3 inches
Wind
(convective)
 Nil
 Below Significant
Weather Alert
 Significant Weather
Alert
 Severe Wind Likely
 75 mph
 Derecho
Tornado
 Nil
Cold Air
Funnels		 Chance
 Likely Tornado < F4
 F4-F5
Winter Weather
 Nil
 Mentioned
 Below Winter Weather
Advisory Criteria
 Advisory
or Watch
 Warning
 Paralyzing Winter Weather
(ie., 1 inch or more ice or
blizzard w/ heavy snow)
River Flood
 Nil
Action Stage
  Likely
 Flood Warning
(minor-moderate)
 Major
Flooding
 Record Flooding
Flood/Flash flood
 Nil
Flood Warnings Possible
(FLW)
 Likely Flood Warnings (FLW);
Possible Flash Flood Warnings (FFW), Flood/Flash Flood Watches (FFA)
 Widespread Flooding,
or high probability of Flash Flood Warnings (FFW)
 Dam Break/
Catastrophic Flooding
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