As we reach the summer solstice, which is the longest stretch of daylight on a single day of the year, we find that summer has definitely taken hold. This usually means easier forecasting as the general weather pattern becomes less active. In the last forecast we saw it begin with several rounds of severe weather across both Manitoba and Saskatchewan and the forecasted area of low pressure played out almost exactly as predicted. The first half of this week saw a return to very warm weather as a building ridge combined with an area of low pressure to our west and allowed temperatures to soar back into the low 30s.
This forecast period will start off with the western low tracking from northern Alberta southeastward toward the Great Lakes. This system will bring the chance of thunderstorms late on Wednesday or early Thursday as a cold front pushes the warm air off to the east. Thursday, Friday and Saturday will see a mix of sun and clouds as the low slowly shifts eastward. Temperatures will cool down behind the low with daytime highs making it into the low 20s and overnight lows falling to around 12 C.
Over the weekend the weather models show an upper ridge rebuilding to our west, then slowly shifting east through the week of June 21. Expect mainly sunny skies with daytime highs climbing back into the low 30s by mid-week. With the increasing heat we will also see increasing humidity. This will lead to a good chance of late-afternoon showers and thunderstorms by Wednesday.
Looking further ahead, the models show typical summer weather continuing, with temperatures running near the top end of the usual temperature range along with the chance for scattered late-day thundershowers almost every day.
Usual temperature range for this period: Highs, 20 to 29 C; lows, 7 to 16 C.