"Summer is the time when one sheds one's tensions with one's clothes, and the right kind of day is jeweled balm for the battered spirit. A few of those days and you can become drunk with the belief that all's right with the world".
Ada Louise Huxtable

The period between June 11th and July 2nd in St. Petersburg, Russia is known as White Nights. This phenomenon is caused by the city’s extreme northern geographic location, which is roughly the same as latitude as Oslo, Norway, the southern tip of Greenland and Seward, Alaska.
Saint Petersburg virtual-tour

"In winter I get up at night And dress by yellow candle-light. In summer quite the other way I have to go to bed by day."
Robert Louis Stevenson

The dog days of summer, lasting from July 3rd to August 11th was named by ancient Romans, because it extends from 20 days before to twenty days after the conjunction of Sirius (the dog star) and the sun. They believed that heat from Sirius increased the heat from the sun during this time period.
/ Factmonster

These are the days when birds come back, A very few, a bird or two, To take a backward look. These are the days when skies put on The old, old sophistries of June, - A blue and gold mistake.Oh, fraud that cannot cheat the bee, Almost thy plausibility Induces my belief, Till ranks of seeds their witness bear, And softly through the altered air Hurries a timid leaf! Oh, sacrament of summer days, Oh, last communion in the haze, Permit a child to join, Thy sacred emblems to partake, Thy consecrated bread to break, Taste thine immortal wine!