This 10 part series will detail forecasting tricks that can be used to try to outforecast MOS. Outforecasting MOS is an important skill for a forecaster. MOS stands for Model Output Statistics and they are used as a guide for temperature prediction and precipitation prediction by forecasters. Model consensus is the average of the high temperatures, low temperatures or precipitation amount predicted by several forecast models.


A synthesis is putting all the weather data together, going through a forecasting checklist and using your meteorology knowledge to develop a forecast. Below is a variety of advice to make sure that is integrated into the forecast method:

1. Look for the potential for warmer or cooler air mixing down to the surface to influence high or low temperature

2. Always look at the upstream conditions. Note if the upstream conditions realistically support the MOS high or low temperature

3. Look for the potential of strong radiational cooling that can cause low temperature to go below MOS consensus

4. With light wind and clear skies, the high will tend to go above MOS consensus and the low will tend to go below MOS consensus

5. Make sure frontal passages and precipitation events are timed properly

6. Keep in mind ocean and lake influences if applicable

7. If POP is less than 30% it may include noise in the data and odds are very much pointing toward no rain. Also don't get too excited about forecasting precipitation when the QPF is just 1 or even 2 in some cases

8. If instability is present, thunderstorms can occur even when POP and QPF are fairly low

9. Don't forecast heavy precipitation unless totally convinced

10. Cloud forecasting is hard sometimes and it can make or break the forecast. Do your best. Also, check satellite for actual cloud cover before making forecast

11. Have a handle on mesoscale influences that are important to the forecast area

12. Take snow cover into consideration when making the temperature forecast if applicable

13. Note what the expected weather is when the wind blows from certain directions. Be comfortable with the climatology of the region. Know what weather events are typical and which are atypical

14. In many cases it is just fine to take model consensus on high or low temperature

15. Be able to interpret MOS correctly from each model. Be especially comfortable with the QPF categories from each model, wind data, temperature data and POP data

16. Be able to synthesis all of the above. Reason for high or low temperature and precipitation CAT that actually occurs is often multi-faceted

17. Keep a journal each day. Describe the weather that is occurring. Compare your forecast to what actually happens and what each forecast model predicted