Forecast Tip:
When forecasting temperatures, look at the temperatures upstream from the station for which you making a forecast. If they are warmer, that means warmer air is being transported towards your station and the temperature should rise. Put in another way, if there is warm advection occuring at a given station, expect the temperatures to increase. In contrast, if cold advection is occurring at a given station, expect the temperatures to drop.

Temperature advection refers to change in temperature caused by movement of air by the wind. Forecasting temperatures using advection involves looking at the wind direction at your forecasting site and the temperatures upstream (in the direction from which the wind is blowing).

For example, consider the two cities below. Assume that a temperature forecast is being made for the northern station, which has a reported temperature of 45 degrees. The northern station is cooler than the southern station, but the wind directions are the same, out of the south. The wind is, in effect, blowing from the southern station towards the northern one. Over time, the wind will transport the warmer air located at the southern station towards the northern station (into a region of colder air), so expect the temperature at the northern station to rise. This process is called warm advection. When colder air is being transported by the wind into an area of warmer air, this is known as cold advection.

highs and lows

Terms for using data resources. CD-ROM available. Credits and Acknowledgments for WW2010. Department of Atmospheric Sciences (DAS) at the University of Illinois at Urbana-Champaign.

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