The Northern Marianas Emergency Management Office says its continuing to monitor closely the volcano on Anatahan island.
The CNMI Department of Public Health urged people last week with respiratory problems to remain indoors after the continued emitting gas and steam.
The government earlier issued an alert over the sulphur laden winds that enveloped the islands of Saipan and Tinian .
Anatahan is a small volcanic island 120 km north of Saipan.
Last month, the Governor again renewed the emergency declaration on Anatahan, saying the island is still unsafe for human habitation.
The declaration has been in place since May 2003.
The Emergency Management Office's Juan Takai Camacho says Anatahan becomes a real problem for locals when the wind changes.
"If there is a change of wind direction and if it's the northerly wind it will blow a possible ash and gas and so forth to Saipan and extending down to Guam."