Monday 1st July, in Fasli tradition, is the Zoroastrian Rain Festival of Tir Jashan, dedicated to the star deities of Tir and Teshar. Give bracelets made of the seven colours of the rainbow (usually silks). At the end of the festival go to a high place and throw them into the wind. It's also traditional to dance, make merry and splash each other with water. This festival is devoted to the divinity Tir and is associated with the dog-star Sirius and the coming of the rains in Iran and the fertility they bring.
As the Festival is actually on the 13th of Tir, some Zorastrian traditions convert this to 4th July.
Interestingly, yesterday, here in the UK, it was the end of Pride month which is traditionally celebrated with any rainbow adornments. The rainbow bracelet shown here (actually it's nylon not silk, but you get the idea) is shown with permission from Eclectic Shop UK in Hove, who sell them for £1.95 each.
For a list of Joanna's forthcoming Harmony Healing events, see this recent Harmony Healing Event Update.