In 2016, IceCube initiated a system of public real-time alerts that are typically issued within one
minute, following the detection of a neutrino candidate event that is likely to be of astrophysical
origin. The goal of these alerts is to enable multi-messenger observations that may identify the
neutrino source. Through January 31, 2019, a total of 20 public alerts have been issued, with
many of them receiving follow-up observations across multiple wavelength bands. One alert in
particular, IceCube-170922A, was found to be associated with a flaring gamma-ray blazar, TXS
0506+056. This was the first >3 sigma association of a high-energy neutrino with an electromagnetic counterpart. In 2019, the IceCube collaboration is introducing a new set of neutrino
candidate selections that expand the alert program. These new selections provide two alert channels. A "Gold" channel will issue alerts for neutrino candidates at least 50% likely to be of
astrophysical origin and is expected to deliver ∼10 alerts per year. Additionally a more frequent
"Bronze" channel will provide ∼20 alerts per year for neutrino candidates that are between 30%
and 50% likely to be of astrophysical origin. We present the neutrino event selections used to
generate these alerts, the expected alert rates, and a description of the alert message.