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%

Other examples:

Where	When	Temp	RH	ReelFeel
Somerville	6 AM July 18, '13	72°	97%
Somerville	5 PM July 18, '13	96°	46%	105°
Bridgewater	3 PM July 25, '16	95°	57%	112°
Sacramento	5 PM July 28, '15	106°	12%
Bridgewater	4 PM sept 10, '16	93°	51%	100°

See Friendly Forecast Weather Archive

Others: Nov, Dec 5 Note: Andover, NJ was a better match for Martinsville, than the AccuWeather default for 24 hr hist which was Trenton.

Sacramento High Temp

	Record	normal	2001	2002	2003	2004	2005	2006	2007	2008	2009	2010
June	115	87					98	105	102	101	105	103
July	114	93	107	104	105	99	105	111	107	110	108
Aug	111	91					102	99	105	107	108

Somerville NJ

Sample at my place:
Aug. 2013 upstairs
  AC on: Humidity - 35%; Temp - 75° inside
  Outside Air:  Humidity - 40%; Temp - 72° inside 11PM  65° outside 
                Humidity - 43%; Temp - 66° inside 8:30AM 63° outside

ReelFeel California vs New Jersey
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