The chart color codes intensity (category based on Saffir-Simpson scale):
Type Category Pressure Winds Surge Line Color
mb knts mph ft
Depression TD ----- < 34 < 39 ----- Green
Tropical Storm TS ----- 34- 63 39- 73 ----- Yellow
Hurricane 1 > 980 64- 82 74- 95 4- 5 Red
Hurricane 2 965-980 83- 95 96-110 6- 8 Light Red
Hurricane 3 945-965 96-112 111-130 9-12 Magenta
Hurricane 4 920-945 113-134 131-155 13-18 Light Magenta
Hurricane 5 < 920 > 134 > 155 > 18 White