1. Winter Weather Forecasting A mini crash course for ATMO 456

2. Assuming there’s precip, what’s important for type? It’s all about freezing layers the precip will fall through It’s all about freezing layers the precip will fall through What’s the average temp of the layer? What’s the average temp of the layer? How thick is the layer (related to the question above, you’ll see later)? How thick is the layer (related to the question above, you’ll see later)? How close is it to the ground? How close is it to the ground? Are there more than one? Are there more than one?

3. Sounding data is most useful if you can get it…

5. Cross sections are good too…

7. Partial thickness criteria

8. Rules of thumb for snow Ratios of snow to liquid water can vary dramatically (higher for dryer snow) Ratios of snow to liquid water can vary dramatically (higher for dryer snow) Typically use PWx10=snowfall/12hrs Typically use PWx10=snowfall/12hrs If T~32F, snow will be heavier/wetter, use PWx5=snowfall/12hrs If T~32F, snow will be heavier/wetter, use PWx5=snowfall/12hrs

9. Conclusion Will you have precip? Will you have precip? What kind will it be? What kind will it be? How much will you have? How much will you have?