We have not been subjected to extreme heat this summer. In fact, through June 18, we are about 0.2 degrees below normal for the month. That appears to be about to change as a massive ridge of high pressure will be in place over the central United States by the time you read this.
We suspect that will mean our first few days of temperatures over 90 degrees during this week. Interestingly, the circumstances leading to this rather usual onset of summertime heat may be pretty unusual.
It appears that an incredible heat wave in Alaska last week (June 16-19) may have set the stage for our coming warm week. The towns of McGrath and Valdez, Alaska, were both over 90 degrees last week (20 and 17 degrees above normal, respectively). There were numerous other reports of temperatures over 90 in Alaska last week — the highest being 96 near Denali National Park.
Valdez had an overnight low of only 69 on June 17.
All of this unusually warm Alaska weather was associated with an incredibly unusual ridge of high pressure at about three miles above the ground. Such a feature keeps the skies clear and, coupled with the very long days in central Alaska near the summer solstice and flow down the sides of the high mountains, the temperatures were able to soar. The evolution of the Alaskan ridge is the main connection between last week’s heat in Alaska and our heat this week.