National Weather Service United States Department of Commerce

Moke Impacts Hawaii; Severe Thunderstorms and Heavy Rainfall from the Great Basin to the Plains

Heavy rain and gusty winds from Tropical Storm Moke will impact the Big Island into Monday, risking life-threatening flooding and mudslides in windward and southeast areas. Severe thunderstorms are expected across the northern Rockies/Plains and northern Great Basin. Dangerous heat persists across the Southern Plains and Lower Mississippi Valley, building further into the Southwest by midweek. 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.