The Tau Herculids is a meteor shower occurring from May 19 - June 19. The discovery of the Tau Herculids shower followed the discovery of its parent comet. It was in 1930 when, during a minor planet survey, photographic plates exposed by Schassmann and Wachmann revealed a new comet (comet 73P/Schwassmann-Wachmann 3). Meteors belonging to the Tau Herculids were observed a short time later after an astronomer at the Kwassan Observatory in Kyoto, calculated a preliminary orbit from which a colleague predicted a meteor shower that would peak on June 9.
Tau Herculid meteors are only seen when the Earth passes through a filament produced by the comet during previous returns, and predictions suggest that we might have an opportunity to see Tau Herculids in 2017 (Mikhail Maslov). Tau-Herculids: prediction of activity
This year comet 73P/Schwassmann-Wachmann 3 passes its perihelion, and its orbit lies at -0.014 AU from the Earth orbit. Only one dense trail passes relatively close to the Earth, its 1941 trail, and the time of maximum is May 30 at 17:42 UT. Since trail still passes quite far from the Earth it is reported as a “boundary” case and we may see no activity at all. However, if we are lucky and the Tau Herculids are active then we can expect to see some bright meteors. According to the IMO, the radiant is most favourable for observers in South and Eastern Africa, the Middle East, and most of Asia, but we will be looking out regardless. A strong tau-Herculid shower is predicted for 2022.
More details are available on the IMO website.