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Snow analyses

WPC snow depth analysis

24 hour analysis produced every 6 hours?

Email from Trevor (Feb 11, 2016):

For sub-24-h periods, WPC creates their own snowfall analysis using 1-h Stage-IV QPE, identifying areas where RAP profiles indicate a precipitation type of snow, and multiplying QPE there by 10 (2:1 for sleet).  Given the 10:1 ratio, this isn't a good way to verify HRRR forecasts that use a variable snow ratio algorithm.  The hourly Stage-IV is also radar-based and uses virtually no observations.  So you could certainly use this analysis to test out MET/MODE on HRRR snowfall, but we would need to take any results with a grain of salt. Mike Bodner is willing to provide the sub-24-h analyses, though he needs to find a way to convert from GEMPAK format.  I'll put you both in touch when he makes some progress there.

UPDATE from Mike (29 Feb):

I made a large tar file of all the verification data and uploaded on the directory you created (our ftp site). The data is through Feb 26 (there's a 2/2 day lag due to QC'd Stage 4 availability.

Starting around Feb 1 or 2, I started writing out the 6 and 24 hr fields on the grid. Prior to this, the 1-hour only is listed. However, GEMPAK will read and make a 6 and 24 hour on the fly.

Data: dakota:/d3/projects/USWRP_ENSHAZ/WPC_Snowfall_Analysis

NOHRSC: http://www.nohrsc.noaa.gov/nsa/

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