You say the source data but you don't say whether you will use table data or the graph. There appears to be differences eg 22nd shows a reading of 83 but graph has label saying high was 82. Similarly 24th has 3 readings of 83 but graph shows 82. Similarly May 8th.

I think the table data should be used: There are other data sources which have the same hourly readings but also have a max for temperatures between these hourly readings which show 84
https://forecast.weather.gov/product.php?site=NWS&issuedby=NYC&product=CF6&format=CI&version=1&glossary=0

https://w1.weather.gov/data/obhistory/KNYC.html

I think this is the source data for your source.

You cannot use those 84 readings between hourly readings as that data isn't on your resolution source page but I think it shows the table data is the data you should use not the labels on the graphs which appear to be the ones that are misstated.

Please can you confirm which will be used. @SteveSokolowski

I should also point out that the graph line does seem to go to 83 but the labels say 82.

@ChristopherRandles Not the most precise product. Graphing is hard though.

@ChristopherRandles The numbers have to be the ones to be used. Charts are generated from raw numbers.