The calendar summer officially begins this Sunday /June 21, 2009@ 146 AM/ and it’s also Father’s Day (so we’ll try for some pleasant weather). Look for high temperatures on this first official day of summer to actually be around normal /upper 70s to lower 80s/. Many people probably have been wondering since the beginning of June (a summer month), where’s our summer weather? With just a hand full of 80s this year and none, I might add this June thus far, is it ever going to warm up? The average temperature through mid June /16th/ at Detroit is a cool 62.9 /-4.5/. Flint is worse at 59.8 /-4.8/ while Saginaw sits at 60.1 /-5.1/. If these numbers were to remain constant through the end of the month, this would be the second coldest June on record at Detroit and the coldest June recorded at Flint and Saginaw. Of course this shouldn’t happen since just climatologically, the second half of June is typically warmer than the first but more to the point meteorologically, things (temperatures) are looking up! I discussed this and other analogue Junes a few weeks ago in our Summer Outlook ;
“The stubbornness of the trough in Canada this spring along with some of the cold June’s found gives a little more credence to the warmer temperatures mid‐late season. Also, our recent guidance is hinting at a warm‐up toward the middle of June and thus, it looks as though the middle of June hopefully should begin our summer‐like weather. This not only was that seen in some of our recent analogue Junes but it also showed up on the composite trend for June, where temperatures actually averaged above normal.”
Our latest guidance (500mb upper wind pattern, above) for the 6-10 day (and also the 10-14 day) outlook continues to paint a warmer regime (especially relative to the first half of June) as it has for awhile now. Check out the projected developing upper level ridge of high pressure over the mid part of the country (and mean wind flow) on the map during the second half of the month, while the upper low pressure trough gets booted east and weakens. However, don’t look for the large Canadian upper low (over Northeast Canada) mainly responsible for the cool June thus far, to take a lengthy vacation any time soon. It is expected to remain a key player, albeit somewhat less often, as the summer evolves.