Rules
Points System
Attention: The more points the better!
Only tornadoes over land within the outlook region will be considered.
R1: Chance Tornado
Non-zero risk for localized tornadic activity.
Maximum of 5 pts.
Color: Black
If a Tornado(s) occurs within R1
Points = ( X / A1 ) * 5
A1 = (R1 Area) / 1000
X = Number of Tornadoes (EF0-5) Within R1
If a Tornado(s) occurs outside R1 (aka within R0)
Points = - 0.25 * X
X = Number of Tornado(s) Outside R1
If no Tornado Occurs within R1
Points = -0.5
R2: Tornado Likely
Increased confidence in isolated to scattered tornadic activity, one or two of which could be strong.
Criteria: 1 to 5 tornadoes
Maximum of 10 pts.
Color: Yellow
If Criteria is met
Points = ( X / A2 ) * 10 * (1 + Y * 0.1)
A2 = (R2 Area) / 1000
X = Number of Tornadoes (EF0-5) within R2
Y = Number of EF2+ tornadoes within R2, up to a maximum of 2 tornadoes
If Criteria is NOT met
Points = (A2 / X ) * ( 1.15 - Y * 0.02) - 0.5 * ( X - 5 )
If no Tornado Occurs within R2
Points = -1
R3: Tornado Outbreak
High confidence that numerous tornadoes will occur, some of which could be strong and long tracked.
Criteria: 6 or more tornadoes
Color: Red
If the criteria is met
Points = ( X / A3 ) * 15 * ( 1 + 0.15 * Y )
A3 = (R3 Area) / 1000
X = Number of Tornadoes
Y = Number of EF2+ tornadoes within R3
If the criteria is not met
Points = ( X / A3 ) * 15 * ( 1 + 0.15 * Y ) - ( 6 - X )
If no Tornado Occurs within R3
Points = - 4
No Tornado Risk Issued
If No Tornado Occurs
Points = 0
If a Tornado(s) Occurs
Points = -0.5 * Number of Tornadoes
Map Error
Incompliant submissions will be treated as "No Tornado Risk Issued"
Notes & Known Faults
Area values provided by Google MyMaps in square kilometers
Areas are scaled down
Penalty for missing a tornado is the same regardless of displacement from R1. This is done to simplify the scoring process.
Sample Score
Outlook Issued for May 20th 2022
A Chance, Slight, and Outbreak risks have been deployed.
Outbreak is must be within Likely and Likely must be within Chance unless a polygon is adjacent to the forecast region border
Outlook overlayed with Confirmed Tornadoes.
Outbreak: 6 tornadoes
Likely: 2 tornadoes
Chance: 1 tornado
Outside: 0 tornado
Total Tornado Count: 9
Tallying Points
Tornadoes outside Chance
X= 1
Points = -0.25 * X
Points = -0.25 * 1
Points = -0.25
Tornadoes Within Chance
R1 Area = R1 Area - R2 Area
= 60 000 - 35 000
= 25 000 km2
A1 = 25 000 / 1000 = 25
Points = X / A1 * 5
= 1 / 25 * 5
= 0.2
Tornadoes Within Likely
R2 Area = R3 - R2
= 35 000 - 23 000 = 12 000 km2
A2 = 12 000 / 1000 = 12
Points = ( X / A2 ) * 10 * (1 + Y * 0.1)
= ( 1 / 12 ) * 10 * ( 1 + 0 * 0.1 )
= 0.83
Tornadoes Within Outbreak
R3 Area = 23 000 km2
A2 = 23 000 / 1000 = 23
Criteria Check:
X = 6 =< 6, no penalty
Points = ( X / A3 ) * 15 * ( 1 + Y * 0.15 )
= ( 6 / 23 ) * 15 * 1.3
= 5.09
Total Score
Total = R0 + Chance + Likely + Outbreak
= -0.25 + 0.2 + 0.83 + 5.09
Total = 5.87 pts