The year to date has seen much lower rainfall than last year. For grass to grow well a certain level of moisture is required, any shortfall of moisture and the grass will turn brown as it conserves energy. Higher temperatures also put the grass under stress. A healthy lawn will naturally show these signs but will recover quickly as the plant and root structure are stronger.
Some tips to help your lawn through the summer:
Grass needs moisture to grow and if we get a long dry period it will help if you are able to water the lawn. A good water once per week will help,having a few days between watering allows the soil to dry out and encourages the roots to go deeper searching for moisture. Watering early or late in the day will reduce any evaporation. A tip to get even coverage is to place a container on the grass under the sprinkler and keep watering until it has reached @1 inch and then move the sprinkler and measure again.