2020-09-10 Dear potential HLPW-4 participant, The deadline for signing up to be on a Technology Focus Group (TFG) is today. https://www.surveymonkey.com/r/GMGW3-HLPW4-Intent no later than September 10, 2020. *You should only sign up for a TFG if you are willing to join as an ACTIVE PARTICIPANT.* This means committing to doing work (like running cases), participating in on-line TFG meetings, and sharing your results with others in your TFG during the 6-8 months leading up to the workshop. Your results will be a part of the summary put together by the organizers of your TFG, and presented by them at the workshop. If you are not a member of a TFG, then your status is OBSERVER. Observers are free to run the test cases, use the grids, etc. But their results will not be included in the collective summaries presented at the workshop. Observers can also do nothing - just observe. Like everyone else, observers can attend the HLPW-4 workshop and join in the discussions there. Observers need do nothing at this time. Tentative dates have been posted to the https://hiliftpw.larc.nasa.gov website. Geometries, Test Cases, and Gridding Guidelines will be publicly available around mid-October, and committee-provided grids should be available in the Oct-Nov timeframe. Other timeframes (such as availability of experimental data) will be posted when we have a better notion. See the FAQs page on the HLPW website for the answers to commonly-asked questions.