On Sunday alone, nine drowning deaths were reported nationwide, up from four a day earlier, according to the Government Centre for Security (RCB).
Since the beginning of April, 93 people have drowned throughout the country, state news agency PAP reported, citing police statistics.
According to officials, alcohol is among the main causes of swimmers drowning in Poland.
Deaths often occur in bathing areas not patrolled by lifeguards.
With Thursday, June 16, a public holiday, many Poles took Friday off to enjoy an extended break from work.
(gs)
Source: IAR, PAP, TVP Info, statystyka.policja.pl