Our relatively mild weather has come to an end, as we have quite possibly seen the last of the low 90 degree days for several months.
The milder temps will be replaced by record breaking heat this weekend and next week, possibly of a long duration. Temps appear to peak Monday-Wednesday of next week.
As you can see above, the temperatures will climb each day through Monday or Tuesday of next week, possibly reaching 120 degrees in Palm Springs next Tuesday.
As you may recall, we experienced a heat wave last year at the exact same time, where the temps reached a searing 122 degrees on June 20th. Many trees were "burned" during that two day event, with weak ficus and over pruned trees bearing the brunt on the damage during that episode. Last years event was followed by a rapid increase in humidity. Details below:
At this time, a rise in humidity does not appear likely. However, a shallow "gulf surge" from the Gulf of California is always a remote possibility if the wind flow turns southeasterly at some point over the next 7 days. This will need to be monitored. At this point though, low humidity is expected during this heat event, with dewpoints expected to remain under 50-55 degrees. A dewpoint under 55 degrees will allow evaporative coolers to continue to function, for those who utilize them.
It appears the high pressure system responsible for the heat wave will be centered over the Phoenix area. This will allow temperatures there to possibly climb a bit higher than our area, possibly reaching 123 degrees early next week. If the high pressure system were to drift west over our area, this could allow our temps to climb higher than 120. These details are likely as the upcoming weekend approaches and the forecast becomes more reliable.
If this high pressure were to drift a bit north, we could see our first summer monsoon flow. However, the deep southeast flow is not expected for the next 7 days. As we approach July, southeast upper level wind flow becomes more and more common, accompanied by afternoon and evening cloudiness, and isolated thunderstorm activity. This generally occurs in late June or early July.
In the meantime, use common sense, and avoid strenuous outdoor activity during afternoon and early nighttime hours. There have been several fatalities due to heat already this season.
The longest day of the year - known as the summer solstice - will be a memorable one yet again this year! Be safe out there, fellow desert dwellers!