... Cold front crosses into the evening followed by an upper level system Saturday. Upper trough Monday. Weak high pressure midweek.
NEAR TERM /THROUGH SATURDAY/... As of 115 PM Friday...
Several bands of showers will pivot through for the remainder of the afternoon with the final one associated with the actual cold front late this afternoon and early evening. Rainfall amounts may exceed an inch across portions of southeast OH and especially northern WV this evening which may result in localized high water. Some of the usual trouble creeks in southeast OH will have to be monitored for exceeding bankfull tonight as well.
50-60 kt low level jet gradually shifts northeast this afternoon, with much of this will remaining aloft given WAA upglide. Some downslope gusts to 35 kts on the west facing slopes will continue. I'm not seeing advisory criteria gusts on any high elevation observation but will leave it up for now, especially with the jet still overhead.
Flow remains generally out of the southwest overnight as near vertically stacked upper low tracks into the mid OH Valley. A decent dry air intrusion will pivot into the region though some weak lift remains in the moist low levels for some spotty showers or drizzle. Temperatures will be slow to fall across the Lowlands as the higher ridges in the mountains drop to near freezing by morning. With the cloud layer remaining below the height needed for ice nuclei, patchy freezing drizzle may develop across the highest ridgetops for a time tomorrow morning.
Upper level system will wobble into the Lakes region during the day tomorrow with weak CAA continuing. The cloud layer depth will increase just enough in the afternoon such that any freezing drizzle across the high mountain tops will transition to snow showers or even graupel given the weak instability in the layer. The Lowlands will continue to dodge scattered showers as temperatures struggle to cool.
SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/... As of 225 PM Friday...
Wrap around moisture from the upper air low pressure system will continue to bring scattered snow showers across the lower elevations. These will mix with rain during daylight hours as temperatures will likely climb a few degrees above freezing both Sunday and Monday. Some grassy accumulations are possible in the lowlands, and the mountains are still on track for a few inches. The fetch of the low level moisture without a moisture source to draw from like Lake Michigan and the westerly direction of the flow will make the upslope for the higher elevations far from perfect or efficient. Snow amounts in future forecasts are likely to fluctuate as temperatures do. In the end, the changes to the short term are minor as we deal with another system that has difficulty generating and appreciable cold air.
LONG TERM /MONDAY THROUGH FRIDAY/... As of 225 PM Friday...
Another trough axis aloft drops in from the north in the cyclonic flow from the previous upper low, coupled with a low level return feed of moisture from the southwest. This warrants POPs back in the region for primarily the mountains that could linger into Monday night. Flow aloft turns zonal, the airmass modifies slightly, and progressive weak systems pepper the extended with overall little fanfare through Friday.