Lake Effect Storm Iron
Output from the workstation ETA model

Below you will find some comparisons of model output from our workstation ETA model and radar data taken from the Montague radar.  The first three images compare model data with radar data at one hour in the storm.  The thumbnail at the bottom of this page will take you to a link that is a loop of model data and radar data at 1-hour intervals through 12 hours or so of this storm.  It is some pretty interesting data!

It is amazing to see how well the model did here.  Now, that is not to say that numerical models do this well in every event.  In fact, our forecaster's assessments of the mesoscale models for lake snows suggest that they hit the big ones pretty well with location and movement of the snowband, but are not very accurate in QPF,  the amount of precipitation produced.  In addition, when you begin to deal with more subtle events, numerical models may miss the event altogether.

It is the forecaster's responsibility to decide when and where these models may be going awry.  The forecast process involves the combination of several forecasters, working together as a team, analyzing all available data, using the best practices of forecast knowledge, rules of thumb, pattern recognition, and the latest technology to develop the forecast for what the atmosphere will look like in the future.  Hopefully, the new technology that is developed and used in NWS forecast offices will continue to improve the final product for our users.    

 

Workstation ETA 1-hour Precip. (.01 inches) ending 1:00PM Thu, Jan 29th.
Here you can see the model output of liquid-equivalent precipitation for a 1-hour timeframe ending at 1:00Pm on Thursday, January 29th.  The edges of the contours are not smoothed, they are a result of the grid spacing at this scale.  Don't forget, we are working on a scale of weather features that is far below the large scale weather systems that make the weather.  The heavier snow from this band is only about 10 miles wide, on the scale of a large summertime thunderstorm!

 

Montague radar reflectivity at 1:00PM on Thu, Jan 29th.
Here you can see the radar output from the Montague radar.  The radar will not see the entire snowband, it eventually overshoots the tops of the storm as the beam gets farther away.  That is why we use a network of radars to monitor the action.

 

Workstation ETA 1-hour Precip. (.01 inches) ending 1:00PM Thu, Jan 29th.
and
Montague radar reflectivity at 1:00PM on Thu, Jan 29th.
Here you can see the model output of liquid-equivalent precipitation for a 1-hour timeframe ending at 1:00Pm on Thursday, January 29th and the corresponding real-world weather, the Montague radar reflectivity at 1:00PM.  The model simulation of where the snowband should be during that hour before this radar image was taken, shows amazingly good agreement with  the real world!  

 

Click on the link below get a great loop of the storm

12-hour loop of model QPF and KTYX radar data