Industry leaders said the 24-hour walkout by Aslef union members on Saturday will coincide with another busy weekend amid a series of Premier League games.
Among the companies affected are West Midlands Trains, which runs London Northwestern Railway and West Midlands Railway, which runs services in the region.
Alongside that company is Avanti West Coast which will be affected on Saturday and on Sunday as it slashed its timetables and suspended ticket sales amid strikes.
The train company, which will be impacted on Saturday, will run as few as four trains per hour from Sunday as leaders hit out at "unofficial strike action" by drivers.
In a letter to the rail industry, seen by the PA news agency, Avanti West Coast managing director Phil Whittingham wrote that the "current industrial relations climate" has resulted in "severe staff shortages in some grades through increased sickness levels, as well as unofficial strike action by Aslef members".
He explained that the operator normally ran around 400 trains per week with drivers voluntarily working on their rest days - for extra pay - but that has "dropped suddenly to fewer than 50".
Mr Whittingham wrote that the previous level of rest day working is "necessary" while more than 250 new drivers are recruited and trained.
He went on: "The reduced timetable is being introduced to ensure a reliable service is delivered so our customers can travel with greater certainty.
"This decision was not taken lightly, and we are sorry for the enormous frustration and inconvenience this will cause."
Passengers who have already bought tickets for trains that are removed from the timetable will be able to travel on the service before or after their booked train.
If they no longer want to travel they can claim a full, fee-free refund from the point of purchase.
Aslef has insisted that its members at Avanti West Coast are not involved in strike action before a walkout on Saturday in a long-running dispute over pay and conditions.
Timetables will be published on Tuesday, August 9, but passengers are being advised to follow the latest travel advice, check before they set off, and allow extra time for their journey.
Other companies not involved in the strike will be running trains, but these are expected to be busy.
The strikes will affect Arriva Rail London, Avanti West Coast, Crosscountry, Greater Anglia (including Stansted Express), Great Western, Hull Trains, LNER, London Overground, Southeastern and West Midlands Trains.
Passengers with advance, off-peak or anytime tickets affected by the strike can use their ticket either on the day before the date on the ticket, or up to and including Tuesday, August 16, or can change their tickets to travel on an alternate date, or get a refund if their train is cancelled or rescheduled.
Further strike action by the Rail, Maritime and Transport (RMT) union, the Transport Salaried Staffs Association (TSSA) and Unite has been announced for August 18 and 20, as well as a separate RMT walkout on London Underground on August 19.