Timely tsunami forecasting and dissemination of warnings are challenging tasks, especially for near-field tsunamis, which can arrive onshore in a few minutes (National Research Council, 2011). For example, the 1960 Chile tsunami (M W 9.5) arrived on Chilean coasts about 15-20 min after the earthquake, and the earthquake and the subsequent tsunami took 1,655 lives (Igarashi et al., 2011). The 2011 Tohoku (Japan) tsunami (M W 9.0) also hit the Japanese mainland 20 min after the earthquake, killing 15,641 people (Mori et al., 2011). Given that the evacuation starting time is one of the key factors related to fatality rates (Yun & Hamada, 2015), it is critical to minimize the time required for tsunami forecasting.