The Lehigh Valley/Berks Area Air Quality Forecast for Thursday, March 20, 2008
Fine Particulates (PM 2.5) – Code GREEN **First Day of Spring!* Regional Maximum PM 2.5 Concentrations: Tuesday, March 18, 2008: PM 2.5 – GREEN (29 AQI or 8.3 µg/m3) Short-Term Discussion: Clouds, showers and fog have crept in across most of the forecast area. A Flood Watch has been posted for Lehigh and Northampton counties as an area of low pressure moves towards our region. This system could trigger heavy rains, gusty winds and possibly a rumble of thunder later tonight. Fine-particulate concentrations are rising in portions of Berks County though numbers are expected to fall later this evening. Cloudy with fog and a possible thunderstorm overnight; rain could be heavy causing some localized flooding. Winds will increase as temperatures fall into the low 40s. Mostly cloudy early with gusty winds and some lingering showers. Skies will clear gradually by the afternoon though winds will remain brisk with temperatures only expected reach the mid to upper 40s. Strong northwesterly winds and drier air will help keep Thursday’s fine-particulate concentrations in the code GREEN (good) range. Extended: Once this system clears out we should see an extended period with little or no significant precipitation except for a weak low projected to cross the Mid-Atlantic on Saturday. This system may produce some light mixed precipitation. Temperatures should run a bit lower than average this weekend as relatively cold air sits over the eastern half of the country. The models are beginning to pick up an interesting storm system for early next week, but we’ll just have to wait to see what happens. For now we expect air-quality readings to remain mainly in the good range for the extended period.
