Even on Monday of this week, it was already becoming apparent this next weekend would again present a challenge to meteorologists in the forecasting process…more on that in a moment.
Another unseasonably cold area of low pressure near the Great Lakes is again bringing well below average temperatures to the Great Lakes and parts of the midwest. As the difference in temperature between the warm lake waters (and, during the day, the somewhat heated land) and the cold air about a mile up increases, the more unstable/”bubbly” the lower atmosphere will become. Water vapor will be lifted up into the cold air, condense, and produces showers and some thundershowers over the Great Lakes and parts of our region. Some tshowers may contain small hail, and this temperature lapse/dropoff rate will also make conditions more favorable for a few waterspouts by Wednesday. After an unsettled Thursday, the atmosphere should be settling down Thursday night into most of Friday, but not for long.
On Saturday, a poorly organized area of low pressure to our SW will begin to feed moisture up through Ohio & PA into our region. This will result in an increasing likelihood of at least a few showers & tshowers, with chances currently (Tuesday post) looking greater over the hills to the S & SE. Similar conditions may prevail again on Sunday. At this point, neither day is looking to be a washout. So, it’s still possible we could end up as fortunate as we were during this past weekend. However, virtually every computer model shows SOME convection/shower & tshower development getting to portions of WNY at times during the weekend. That means no meteorologist could objectively predict on this Tuesday that we WILL be mainly rainfree. Both you and I will have to be patient for the details to emerge, as the mechanism to make these showers will be somewhat weak and diffuse.
After we’re through with this spate of September-like weather through Thursday, temperatures will edge back up closer to average on Friday into early next week. Most extended range guidance suggests more seasonable temperatures more of the time as we move toward mid-August. But I also have to tell you that the ups-and-downs which will probably occur in that time range can not be foreseen this far in advance.