Contents:

National Weather Service (NWS) Heat Index Risks:

• Less than 80 degrees--Comfortable by most standards
• 80 to 90 degrees--Caution: fatigue with prolonged exposure and activity, use caution
• 90 to 104 degrees--Extreme Caution: sunstroke, heat cramps, heat exhaustion possible
• 105 to 129 degrees--Danger: sunstroke, heat cramps, heat exhaustion likely
• Over 130 degrees--Extreme Danger: will result in heatstroke or sunstroke quickly.

Somerville, NJ and Sacramento, CA examples:

July	Average (F)	Record Hi	Humid
New Jersey	85°	105°	54%
Sacramento	94°	114°	30%

The ReelFeel® index in Sacramento is similar to that in New Jersey in the afternoon, but the lower temperature and humidity at night in Sacramento result in a 10-15° cooler ReelFeel at other times.
The Heat Index during the day in Sacramento is lower than the actual temperature because it is computed based on a normal (20-40%) humidity and Sacramento humidity is lower.

Somerville New Jersey 24 Hours from 6pm Jun. 9, 2008

Time	Temp (° F)	RealFeel (° F)	Rel. Hum.	Wind Dir.	Wind Speed	Press. (in)	Precip. (in)	Vis. (Miles)	Weather
6am	72	78	90	N	4	29.88	0	3	l/fog
7am	77	91	81	CLM	1	29.9	0	5	haze
8am	84	103	69	CLM	1	29.9	0	5	haze
9am	87	105	64	SSE	4	29.89	0	5	haze
10am	90	112	57	CLM	1	29.88	0	7	sunny
11am	92	105	46	N	5	29.88	0	9	sunny
Noon	92	102	46	S	6	29.87	0	9	m/sunny
1pm	93	106	49	N	5	29.85	0	8	m/sunny
2pm	95	109	42	CLM	1	29.84	0	9	sunny
3pm	94	106	43	CLM	1	29.82	0	8	sunny
4pm	93	102	47
5pm	92	98	51	S	5	29.78	0	7	sunny
6pm	91	93	46	N	4	29.82	0	10	sunny
7pm	84	92	62	CLM	1	29.83	0	9	clear
8pm	81	90	71	CLM	1	29.84	0	9	clear
9pm	77	86	81	CLM	1	29.85	0	7	clear
10pm	75	85	90	CLM	1	29.86	0	6	clear
11pm	75	84	87	CLM	1	29.86	0	5	clear
Mid	73	82	93	CLM	1	29.87	0	4	clear
1am	72	80	93	CLM	1	29.87	0	4	clear
2am	71	78	93	CLM	1	29.88	0	3	l/fog
3am	70	76	93	CLM	1	29.87	0	4	clear
4am	69	74	92	CLM	1	29.86	0	3	l/fog
5am	69	75	92	CLM	1	29.88	0	3	l/fog

Source: AccuWeather