What does the code MIFG signify in weather reporting?

The code MIFG specifically indicates shallow fog in weather reporting. This type of fog is generally characterized by a maximum vertical visibility that is less than 5/8 statute miles, but it does not completely obscure visibility to the extent that would be associated with more severe forms of fog. Recognizing the coded reports is critical for understanding atmospheric conditions, as they provide vital information for pilots and meteorologists about potential visibility challenges when navigating or forecasting weather.

Understanding that "MIFG" relates to shallow fog helps differentiate it from other types of fog or visibility reports. For instance, while generalized terms like heavy fog might imply more widespread and thicker conditions, "shallow fog" signifies localized areas where visibility is impaired, but to a lesser degree than more intense fog conditions. This nuanced understanding is important for making informed decisions based on current weather conditions.