As of Monday morning, the temperature in downtown Sacramento has reached at least 100 degrees each of the last 6 days. The forecast for Monday afternoon calls for the 7th day of triple-digit heat. If we reach 7 straight days of 100 degrees, it would be just the third time that's happened in Sacramento during the month of June since record-keeping began in 1877.The most recent heat wave ended with a reading of 110 degrees on July 4, 2013.Additionally, a 100-degree high today would make 11 days total with a high of at least 100 degrees this month. That would be the second most for June, behind June of 1981, which had 12 days reach 100 degrees. The Delta breeze has provided some relief with our current round of heat. The average overnight temperature in Sacramento over the past week has been 68 degrees. The last couple of nights have dropped into the low 60s. Overnight cooling significantly lowers the severity of a heat wave because it allows time for our bodies to cool down and recover and it helps to lower the energy needed to keep buildings cool.For an entire year, the average number of 100-degree days in Sacramento is 17. This year's relatively hot start certainly increases the odds of besting that average this year, but above-average heat in June can't be used to indicate conditions for the remainder of the summer. It is worth noting that July is typically the hottest month of the year.The heat is expected to break later this week, leading to a cooler stretch through the holiday weekend. Check the forecast any time online and on the KCRA 3 app.