By Elena Kadvany
Special to the Almanac

Caltrain commuters stressed out by late trains or not knowing exactly when their train will arrive or depart can take a deep breath. Caltrain is testing a system that will tell riders an hour in advance the actual expected arrival and departure times based on real-time data.

Passengers will be able to get the information by message signs and public address systems at the stations, on Caltrain.com, and by signing up for free email and text-message alerts.

The Predictive Arrival/Departure System will work with GPS technology already installed on Caltrain locomotives that can transmit information about a train's speed and location to the Caltrain Central Control Center.

The first round of testing will occur from July 9 through July 13, from 10 a.m. to 3 p.m. During this period, passengers and neighbors may hear live testing announcements. Additional testing is scheduled for August and September.

The system is expected to go live by the end of the year.

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