1. Materials Adapted from The University of Georgia
The Forecast Funnel
METR 2021: Lab 01
Materials Adapted from The University of Georgia (

2. Snellman’s Forecast Funnel

3. Hemispheric
What is the hemispheric pattern and what effect will it have on my forecast?
What is the pattern of the westerlies?
Check 500mb charts
How is the pattern evolving?
Progressive
Stationary
Regressive

4. Hemispheric Tools Constant Pressure Charts Satellite Animation
Isallohypse Charts (500mb)
Departures from normal in height field

5. Synoptic What is the problem of the day?
What and where are the “weather-producing” features?
How well do the numerical models represent these features?
How are the going to evolve?
Relate “features” to conceptual models
Frontal Models
Upper-Level Jet Structure
Baroclinic Leaf (satellite)

6. Synoptic Tools Surface / Upper-Air analyses Satellite NWP (models)
Objective
Subjective
Satellite
NWP (models)
Soundings
Wind Profilers (currently down)
Regional Radar Animations / Lightning Data

7. Mesoscale How does the mesoscale affect my problem of the day?
What is the direction and magnitude of the vertical motion?
Mesoscale convergence zones (radar)
Isentropic analyses
topography
Is the local airmass going to be wet or dry?
How extreme or benign will the weather in my forecast area be?

8. Mesoscale Tools Doppler Radar Lightning Data Mesoanalysis Soundings
Wind Profilers (currently down)
Topography (also local scale)

9. Forecasting time table

10. 0 to +6 hours (Nowcasting )
Extrapolation of regional conditions and systems:
Thunderstorm Development
Fog Dissipation / formation
Time of clearing / clouding
Onset / Ending of precipitation
Rely upon remote sensing and mesoanalysis

11. +6 to +12 hours
Rely on combination of extrapolation and numerical guidance
Everything from previous slide
Precipitation development along front
Influence of shortwave trough entering region
Cloudiness Trend
Temperature Trend

12. +12 to +48 hours Lean more on numerical guidance than extrapolation
Specific timing precipitation onset
Type of precipitation
Specific effects of a shortwave trough
Cold surge / heat wave
Movement of cyclones and anticyclones

13. +48 to +120 hours Almost complete reliance on numerical guidance
Placement of surface systems / upper level features
General statements about
Temperature
Precipitation
Cloud cover
Teleconnections

14. +120 to +240 hours (5-10 days)
Mainly use statistical / climatological models
Use numerical guidance to tweak
Above / Below average temperatures
Above / Below average precipitation
Teleconnections

15. 10 days to 1 month
Almost entirely rely upon statistical / climatological models
Sometimes can use historical analogs
Teleconnections

16. Assignment
Over the next week pick a forecast period for somewhere in the lower 48 states and use the forecast funnel to make a forecast for the location that you picked.  
Please select one or at most two maps from each scale of the funnel and embed the images in a single webpage.  
On the page, please give a short description of the figure that you have included and at the end write a brief discussion of the forecast.  
Finally, at the bottom of the images please give the forecast for the next two days for the chosen location.  
You will not be graded on the accuracy of your forecast, but you will be graded on the quality of the image and whether or not it helps to explain the forecast being made.