Day 4 of Erie, PA (KERI)

After a high of 36F at the beginning, it dropped down to 27F with heavy lake-effect snow this morning and strong winds, though not as strong as modeled (maximum of 29 kt). After a break in the snow, more lake-effect snow occurred as the wind switched from westerly to northwesterly, also causing a slight rise in temperatures due to the wind directly off Lake Erie, despite the overall cold advection. There also appears to be undercatch with the station only reporting 0.09” so far. A stronger band of lake-effect snow with a connection to both Lake Huron and Lake Erie looks weaken later tonight but with still snow showers almost constantly through tomorrow. Temperatures will not vary a lot with stiff winds (though not as strong as today), cloud cover, and the wind off Lake Erie precluding much of a diurnal cycle. The wind will shift from northwesterly to west or west-southwesterly, perhaps reducing the lake moderation slightly, but that cooling effect will probably be canceled out by weak synoptic-scale warm advection. Low will likely occur tonight with the coldest air aloft during any heavier snow bands that bring colder air aloft down to the surface (and that could be when highest winds occur as well). High should occur during the day tomorrow but will depend on how quickly winds shift to west-southwesterly (not off Lake Erie, implying staying colder all day, possibly staying below freezing). 

 

The change in wind direction will also promote a shift to weaker, less intense but more widespread lake-effect snow to a single, more isolated and perhaps more intense band, though intensity limited by the warm advection aloft and the band is unlikely to stay in any one spot for too much accumulation. Again, it’s hard to tell if undercatch will be as severe, though lighter winds and slightly warmer temperatures seem to argue against as much undercatch.

 

Source: PivotalWeather

 

Source: PivotalWeather