As temperatures dip and frost makes a cameo across Pittsburgh, residents may need to scrape their windshields a little earlier than usual. According to the National Weather Service Pittsburgh, PA, a frost advisory in effect until 9 AM EDT this morning puts parts of the area on alert, and it's not over yet; another advisory stretches from 2 AM to 9 AM EDT Friday. Folks around Tucker and Preston counties should brace themselves even more as a Freeze Watch looms over them, bringing the potential for even colder temps.
The weather story doesn't end there; clear skies today bring mostly sunny vistas. With the sun's rays forgone, bringing warmth and turning the eyeball of the sky into an ironic spectator of the chill below, high temperatures are expected to lag around 5 degrees below the usual for this point in October. A certain peace lies in the predictability of this autumn stint—in the calm wind that allows for the formation of river valley fog and in the high pressure nestled above promising another day of dry weather for the latter part of Thursday and through much of Saturday.
Saturday night, however, signals a change in the atmospheric tune as rain chances nudge their way back into the forecast. A weak cold front and an approach from a shortwave trough might not bring the downpour. Still, they could destabilize the tranquility with showers, especially as a surface low meanders across neighboring states and ushers the front back northwards.
Looking ahead to the end of the weekend, showers become a likely companion for Sunday wanderings. The meteorological melody intensifies into next week—with a long-wave trough setting up residence and crafting conditions for scattered showers, specifically more insistent near and north of I-80, says the National Weather Service. "850mb temperatures are progged to drop to -2 to -3 deg C later Monday and Tuesday," they note, which may invite a few snowflakes to mix in with the rain, inviting a wintery tease into the region. Overall, the city is in for a ballet of weather developments wrapping us in layers, nudging us indoors, as the trough begins a tentative retreat by next Wednesday.
For aviators and skyward glancers, Thursday and Friday mornings could present foggy challenges, though northerly winds should dissuade cumulus formations from lingering too long. The outlook points towards cloud cover before the weekend, with increasing potential for ceiling restrictions come Sunday's active front. The sturdy rule of clear skies under high pressure will thus be usurped, submitting to a more variable reign governed by the movements of distant disturbances and local troughs.
