National Weather Service United States Department of Commerce

Snow Continues in the Great Lakes; Above Normal Temperatures in the West

Lake effect snow will continue into the weekend as two more quick moving systems will bring widespread snow to the Upper Great Lakes. High winds are expected across portions of Montana through the weekend. Below normal temperatures will remain in place across much of the southern and eastern U.S., while the western U.S. will experience above normal temperatures. Read More >

HEAT INDEX °F (°C)
  RELATIVE HUMIDITY (%)
Temp. 40 45 50 55 60 65 70 75 80 85 90 95 100
110
(47)
136
(58)
                       
108
(43)
130
(54)
137
(58)
                     
106
(41)
124
(51)
130
(54)
137
(58)
                   
104
(40)
119
(48)
124
(51)
131
(55)
137
(58)
                 
102
(39)
114
(46)
119
(48)
124
(51)
130
(54)
137
(58)
               
100
(38)
109
(43)
114
(46)
118
(48)
124
(51)
129
(54)
136
(58)
             
98
(37)
105
(41)
109
(43)
113
(45)
117
(47)
123
(51)
128
(53)
134
(57)
           
96
(36)
101
(38)
104
(40)
108
(42)
112
(44)
116
(47)
121
(49)
126
(52)
132
(56)
         
94
(34)
97
(36)
100
(38)
103
(39)
106
(41)
110
(43)
114
(46)
119
(48)
124
(51)
129
(54)
135
(57)
     
92
(33)
94
(34)
96
(36)
99
(37)
101
(38)
105
(41)
108
(42)
112
(44)
116
(47)
121
(49)
126
(52)
131
(55)
   
90
(32)
91
(33)
93
(34)
95
(35)
97
(36)
100
(38)
103
(39)
106
(41)
109
(43)
113
(45)
117
(47)
122
(50)
127
(53)
132
(56)
88
(31)
88
(31)
89
(32)
91
(33)
93
(34)
95
(35)
98
(37)
100
(38)
103
(39)
106
(41)
110
(43)
113
(45)
117
(47)
121
(49)
86
(30)
85
(29)
87
(31)
88
(31)
89
(32)
91
(33)
93
(34)
95
(35)
97
(36)
100
(38)
102
(39)
105
(41)
108
(42)
112
(44)
84
(29)
83
(28)
84
(29)
85
(29)
86
(30)
88
(31)
89
(32)
90
(32)
92
(33)
94
(34)
96
(36)
98
(37)
100
(38)
103
(39)
82
(28)
81
(27)
82
(28)
83
(28)
84
(29)
84
(29)
85
(29)
86
(30)
88
(31)
89
(32)
90
(32)
91
(33)
93
(34)
95
(35)
80
(27)
80
(27)
80
(27)
81
(27)
81
(27)
82
(28)
82
(28)
83
(28)
84
(29)
84
(29)
85
(29)
86
(30)
86
(30)
87
(31)

Category Heat Index Possible heat disorders for people in high risk groups
Extreme
Danger
130°F or higher
(54°C or higher)
Heat stroke or sunstroke likely.
Danger 105 - 129°F
(41 - 54°C)
Sunstroke, muscle cramps, and/or heat exhaustion likely. Heatstroke possible with prolonged exposure and/or physical activity.
Extreme
Caution
90 - 105°F
(32 - 41°C)
Sunstroke, muscle cramps, and/or heat exhaustion possible with prolonged exposure and/or physical activity.
Caution 80 - 90°F
(27 - 32°C)
Fatigue possible with prolonged exposure and/or physical activity.