Pittsburgh’s notoriously unpredictable weather is set to make waves this week, with a mix of showers and possible thunderstorms on the horizon. The National Weather Service in Pittsburgh reports that a cold front moving through the region today will likely trigger unsettled and stormy conditions. A brief break is expected on Wednesday as high pressure brings drier weather, but another weak cold front arriving on Thursday could once again bring the chance of rain and thunderstorms.
Forecasters have placed areas from near a line from DUJ to PIT to ZZV, and points east under a "Marginal Risk," or level 1 out of 5, for severe storms today. Along with the stormy forecast, Pittsburghers may also need to prepare for possible localized flash flooding. Showers and thunderstorms are expected today along and ahead of an approaching prefrontal trough and an associated shortwave trough, the National Weather Service reported early this morning. Despite lower Precipitable Water (PWAT) values than usual for much of the region, faster storm motions, attributed to increased flow aloft, aren't ruling out backbuilding or training storm formations that come with a risk of localized flooding.
Looking ahead, patchy fog is expected tonight, followed by a "Dry Wednesday," as stated by the National Weather Service. While Wednesday night is expected to remain dry, another cold front is on the way for Thursday, potentially bringing slight chances for showers and thunderstorms. These predictions hinge on a developing shortwave trough, bolstered by very dry air aloft, that may temper the frequency of updraft growth, compressing precipitation chances to slight.
For those looking to celebrate the first half of the upcoming holiday weekend, the forecast appears promising, with dry weather expected through the first half of the holiday weekend, according to the NWS' long-term outlook. However, as the heat intensifies, Pittsburgh may experience not only higher temperatures but also a resurgence of showers and thunderstorms by Sunday and Monday.
In terms of aviation, while today's storms are predicted to focus south of I-70, the accompanying high rainfall rates may create rapid reductions in visibility. In contrast, a more prevailing westerly flow from storm motion would be favored for any gust around 25-35kts, as the NWS notes. Furthermore, a return to VFR conditions is anticipated by Wednesday afternoon, with a continued watch for isolated showers due to residual moisture.
For continuous updates on weather conditions and potential advisories, the public can refer to the National Weather Service's website at forecast.weather.gov.
