This morning, in the upper fringes of the region (around Cattaraugus Creek), NWS radar in Buffalo is picking up a very narrow band of precipitation that bears a passing resemblance, at first glance anyway, to lake effect. The problem is that Lake Erie is only 49 degrees (9 C) right now. Over Lake Erie, the 850-mb temperature is about -2 C and the 925-mb temp is about 2 C. Though it’s possible for lake effect to form in those conditions, it’s not really all that ideal. The lapse rate is about 1-2 degrees under what is typically needed for good lake effect convection. On top of that, behind that lower level cold pool of air is some moderately warmer air, so I would expect that anything lake-induced will die off fairly quickly.

All in all, once this relatively fast-moving low pressure system moves out today, it will be a quiet, dry weekend. So, without further ado…

Friday

Mostly cloudy skies, possibly with a few breaks of sun. A few showers early in the northern fringes of the region, ending by afternoon. Afternoon highs will be in the upper 40s, about normal for this time of year. Cloudy skies continue into the night, and the significant amount of moisture will hold early morning lows in the upper 30s.

Saturday

Mostly cloudy skies, with a few more breaks of sun, will come our way Saturday. Afternoon highs will reach 50, with lows that night dropping into the 30s.

Sunday

Even more sun, and slightly warmer, with temperatures up in the mid-to-upper 50s.

Thanksgiving Preview

The aforementioned pattern looks like it will hold in place through half of next week, but right on Thanksgiving Day, significantly colder air pushes its way into town. The GFS is forecasting a temperature of about -7 C at 850-mb, which (if the lake temperature holds, and given the current temperatures, I see no reason why it would drop) would put us squarely in the realm of lake effect. Winds appear to be favorable for such a band to form.

Happy holidays.