In reference to your FNL archive products, when we retrieve a map corresponding to a specific
date do we get a model predicted field or an actual one? Interpreting the caption in the lower
part of each figure we would be inclined to think we are dealing with an analysis. When one
looks at the caption on the left side, on the other hand, an initializing date is
indicated and the suspect arises that we are facing a prognostic map.
Most FNL fields are model output analyses. The exceptions are 6-hour
accumulated precipitation and 6-hour average flux values and cloud
cover. The plots give the forecast hour at the bottom (+0 or +6). See
also Table 2 of the FNL README file at
http://www.arl.noaa.gov/ss/transport/archives.html. The label on the
left side of the map, which gives an initialization date, is not correct for our
archive files. It's just giving the date/time of the 1st record in the
file. Historically we've used the same plotting program for both
forecast and archive files and haven't changed this labeling.
Barbara Stunder