Air quality conditions today are very similar to those reported yesterday. However, ozone levels have worsened significantly, several stations mainly in the Great lakes region read unhealthy levels, code red during the afternoon (top left). The large smoke plume also reported yesterday from several fires continues to spread and now is reaching the east coast (top right). Most of this smoke is originated in Utah, Wyoming, Colorado, and Montana where several fires have been taking place for weeks. MODIS true color detected today more fires and smoke plumes in that region (middle). In particular, a broad area of moderately dense smoke extends from Colorado, Wyoming and eastern Montana eastward across the northern Plains into Minnesota where it mixes with clouds in a weather system. The smoke gets caught up in the weather system and has been pulled north over Hudson Bay. Finally, elastic lidar measurements at UMBC show at least three layers of smoke during the day. This smoke was also detected during the past two days but the load of smoke now is way higher that that observed previously.