Several days of fair weather are probably the result of

Warm front that has stalled over an area
A huge low pressure system moving over the area
A cold front that has remained in the area
A warm dry air mass moving over the are

1 answer

Several days of fair weather are probably the result of a warm dry air mass moving over the area. Warm, dry air is typically associated with high pressure systems, which lead to calm, clear skies and stable weather conditions. In contrast, a stalled warm front or a huge low pressure system would likely lead to cloudiness and precipitation. A cold front often brings initial fair weather, but it tends to be followed by instability and potential storms.