Time Zone Shift Disappeared

I have been using an lk script to download weather files and an Excel VBA subroutine to run SAM for a list of photovoltaic plants.
The script worked well and I downloaded 711 weather files and generated hourly MW plant output for an historical year (2009).
Unfortunately, SAM has started to return the time series in GMT and not adjusted by the time zone offset (-8 in my case) as it did before.
Without asking folks to dive into my code, is there something in the setup and execution of SAM that can cause this to occur?  The weather files have the proper value for 'Time Zone' (e.g., -.
I did add a line to my VBA code to retrieve the time zone shift, in order to make time series with shift of -8 and -7 line up.  But that is just a 'get' statement:  
sscvb_data_get_number p_data, "tz", dTimeZoneOffset ' Get UTC time zone offset in hour.
I only use the value to offset a range index by 0 or 1.  I removed that line of code and the issue persists.

Thanks for any advice or solution.

Hi Steven,

Recent updates to the National Solar Radiation Database (NSRDB) are causing some problems with weather file downloads. We are working to resolve those for the next update to SAM 2020.2.29, which we hope to release by the end of this month.

For the latest information on the NSRDB APIs, please see developer.nrel.gov/docs/solar/nsrdb/ .

To track our work resolving this issue in SAM, please see github.com/NREL/SAM/issues/347 .

Best regards,
Paul.

Hi Steven,

One other suggestion is to use the &utc=false parameter in the URL you use to make the NSRDB API call to ensure that the weather file includes the local time zone in the header.

Documentation of the APIs is here:

developer.nrel.gov/docs/solar/nsrdb/psm3-download/

And here:

developer.nrel.gov/docs/solar/nsrdb/

Best regards,
Paul.

Paul, you pointed to the source of my problem.  My query string did not have the utc=false parameter in it.  However, I built my string using the template 'link' that is provided by the json 'nsrdb_data_query.json?api_key=<SAMAPIKEY>&wkt=POINT('... query.  I only did replacements for 'yourapikey' and 'youremail'.  Since my lk script worked properly last month, I think the 'links' were changed, removing the utc=false parameter as the template default.  Regardless, I'm back in business.  Thanks!

Steven

Hi Steven,

Glad that fixed the problem. The NSRDB API is being updated, and some of the parameters have changed. It took me some very careful examining of the links returned by the NSRDB Data Query API and many test calls using various URLs to discover the changes.

I will be updating the sample LK scripts to reflect these changes soon.

Best regards,
Paul.