At the WMO Commission for Basic Systems (CBS) ET-OWFPS Meeting on 22-24 October 2014 in Geneva, a draft document on standardized surface verification of deterministic NWP products was agreed. The document specifies the content of the future exchange of surface scores between global centres and is available here: Standardized Surface Verification for Deterministic NWP.

ECMWF will be collecting and archiving the scores. Data will be exchanged in an ASCII-based format which is simple but flexible and is similar to the format used WMO exchange of upper-air scores.

Data format

Data file consists of score values and corresponding metadata in an ASCII format.

...

If the value of any key is unknown it is encoded as "na". However, every record has to have a valid mean_value (the "v" key); if the value is not known such record should not be included in the data file.

Example

centre=ecmf,model=hr_0001,d=201602,t=00,s=0,st=97146,lat=-4.1,lon=122.43,lam=-4.147,lom=122.484,se=50,me=163,par=tcc,sc=ct,th=2/6,v=0/0/0/0/0/7/0/0/21
s=3,v=0/0/0/0/0/4/0/0/24
s=6,v=0/0/0/0/0/2/0/0/26
t=12,s=12,v=0/0/0/0/0/6/0/0/22
s=15,v=0/0/0/0/0/3/0/0/25
s=18,v=0/0/0/0/0/4/0/0/24
t=00,s=0,sc=mae,th=na,v=60.92
s=3,v=59.92
s=6,v=62.01
t=12,s=12,v=60.59
s=15,v=59.81
s=18,v=62.08
t=00,s=0,sc=me,v=-60.92
s=3,v=-59.92
s=6,v=-62.01
s=9,n=26,v=-66.37
...

...

• sample_size is number of observations used to compute the monthly mean at the given station;
  
• mean_value is the value or values of the score mean computed based on the forecast initiating at time time UTC, verifying in the month yyyymm, for the forecast length forecast_step hours; in case of n_xn contingency table these are the n² values delimited by forward slashes (see the score table above)

Procedures for exchange of data

Coming soon...