Today marked the first official flight for NASA's DISCOVER-AQ campaign and what a day for taking air quality measurements. Although there was plenty of sunshine across the region, calm winds and warm temperatures helped most of the Mid-Atlantic States climb to moderate/Unhealthy for Sensitive Groups PM 2.5 levels .
As atmospheric ridging brought subsiding air into the region, the Planetary Boundary Layer (PBL) remained stable this afternoon. Lidar measurements at UMBC depict the stable PBL, and also yield a spectacular view of layers aloft drifting down into the PBL.
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Below is a photo of NASA's P3B as it flies over the UMBC campus this afternoon.
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High pressure is forecast to slide east off the Mid-Atlantic coast over the weekend, and with the southeasterly wind shift (pulling in more moisture from the Atlantic), elevated poor air quality conditions through Sunday are a possibility. NASA announced today that crews would continue with air quality monitoring efforts over the holiday weekend, as the datasets would be invaluable for the campaign.