What method is used to calculate the 12-hour mean temperature for sea-level pressure adjustments?

The 12-hour mean temperature for sea-level pressure adjustments is calculated using the current temperature and the temperature from 12 hours ago. This method provides a straightforward way to establish a mean temperature over a specific time period by directly comparing the most recent temperature readings with those from 12 hours prior. This approach is beneficial because it takes into account any changes in temperature during that half-day period, leading to a more accurate representation of the average temperature that aligns with pressure adjustments made for forecasting and analysis.

Utilizing the current temperature and the temperature from 12 hours ago allows meteorologists to effectively assess trends in temperature fluctuations, which can impact the interpretation of weather patterns and atmospheric stability. Other methods, such as averaging hourly temperatures over the entire 12 hours, may not accurately reflect significant rapid temperature changes that could occur within that time frame, while considering the high and low temperatures of the day would provide an incomplete picture. Similarly, using just the past 12 hours' high and low temperatures does not adequately capture the continuous variation that could be present between those extremes.