However, the jury is still out on many of these issues, as there is a lack of comprehensive studies. According to data collected by NCSL : -Twenty-one states currently have school districts (with public schools) operating on a four-day week.
In the capital Lisbon average temperatures range from 8 degrees Centigrade in January to 29 degrees Centigrade in July. But it is not unusual to get temperatures well over 30 degrees Centigrade in some summers particularly at the holiday resort of Faro in far south of Portugal.
At most you may see a brief thunderstorm one day during the month. The most rain ever reported in May for a twenty four hour period was 59 mm. Average humidity ranges in Lisbon remain steady during the summer months. Morning relative humidity averages 82% while by evening this drops to 57%.