Commencing on May 23, a dust storm has been affecting the region of Chryse. Dust is now spreading to the south, affecting Valles Marineris, making it into a Regional scale event. As of today, May 26, Hellas and environs are still dust-free. If the pattern of previous Chryse events is followed, dust will spread south over Mare Erythraeum and Argyre, and southeast towards Hellas via Margaritifer Sinus and Noachis. On the western side it is likely that the area around Solis Lacus may also become affected.
Observations are urgently required, though the region of Chryse is now becoming lost over the morning limb from the longitude of the UK in the available observing window.
An update will soon be posted on the Mars Section 2022 blog page.
This event did not last more than a few days, but one never knows how large such an event may become. I tend to wait a day or two to see how an event develops before posting an alert. The location and rapid development of this storm suggested it would reach larger proportions than it eventually did. If you obtain any observations of Mars, whether dusty or not, please send them direct to me. The 2022 blog at the Section website was recently updated. Good observing!