TDS Team,
We have a production TDS system that has been running for a long while (~5 
years) that accesses data for a collection of stations around the US (~41 years 
of hourly data for many variables per station).  When trying to use TDS' 
OpenDAP option to retrieve any record with time-varying data some stations, we 
get a message back with an error message (the variables with only one value 
work fine). The message we get is vague (see below).
Dataset {
    Float64 waveSpreadWindsea[time = 744];
} wis/Pacific/ST81512/1981/WIS-ocean_waves_ST81512_198103.nc;
---------------------------------------------
Error {
    code = 500;
    message = "null";
};
TDS can see there are 744 records (hourly data for one month), yet cannot 
retrieve and send that data back. I have downloaded the NetCDF file for this 
month and have been able to use other tools (HDFView, R, and Python) to read 
the file contents with no issues, yet Thredds is unable to retrieve that data.
For a station immediately adjacent to this location, TDS works completely fine 
in retrieving using OpenDAP.  The file sizes for each station is reasonably 
similar, so it's not like the data is not written correctly.
Here are a couple of links that can be used as references for "working" and 
"not working" in TDS.
Working:
//chldata.erdc.dren.mil/thredds/dodsC/wis/Pacific/ST81512/1981/WIS-ocean_waves_ST81512_198103.nc.ascii?waveSpreadWindsea%5B0:1:743%5D
Not Working:
//chldata.erdc.dren.mil/thredds/dodsC/wis/Pacific/ST81513/1981/WIS-ocean_waves_ST81513_198103.nc.ascii?waveSpreadWindsea%5B0:1:743%5D
There are plenty of other stations which show the same issue.
Would it be possible for someone (TDS developer or otherwise) to assist us in 
tracking down why some stations work and others do not?  We are presently using 
the 5.5 snapsnot with Apache Tomcat 9.0.76 and Java 11.0.19.
Thanks in advance,
Mitchell Brown
Coastal and Hydraulics Laboratory, ERDC
US Army Corps of Engineers