Table 2.

Associations between weather and shootings in Chicago

Variable	% change in shootings	95%CI	Confounders adjusted for:
Temperature (High)a
On weekdays	34.0	(28.1, 40.2)***	n/a
On weekends/holidays	41.6	(34.7, 48.9)***	“
Δ in temperature from historical average	33.8	(29.1, 39.7)***	Prec. Type
Precipitation Type			Temperature
Rain	−4.4	(−10.4, 1.9)	“
Snow	0.1	(−9.3, 12.3)	“
Thunderstorm	−2.2	(−9.8, 5.3)	“
Precipitation Amount b	−4.1	(−9.1, 0.2)	Prec. Type, Temperature
Humidity (Max)a	−0.5	(−3.1, 2.2)	Temperature
Wind (Max)a	−1.8	(−4.7, 1.2)	Prec. Type
Year (Ref = 2012)
2013	−13.0	(−4.4, −20.8)**	n/a
2014	2.8	(−6.3, 12.7)	n/a
2015	18.7	(8.4, 30.0)***	n/a
2016	73.4	(58.7, 89.6)***	n/a

^afor every ten unit increase (°C, %, and km/hr., respectively). ^bfor every 1 cm

* < 0.05, ** < 0.01, *** < 0.001