convert text string to datetime field

A have a date field I convert to a string text field I and then converting to a datetime field. The {varTemp_Date_Time_End_No_Time} is 2015-10-28

DATETIMEVALUE (Text(YEAR( {!varTemp_Date_Time_End_No_Time} )) & “-” & Text(MONTH( {!varTemp_Date_Time_End_No_Time} )) & “-” & Text(DAY( {!varTemp_Date_Time_End_No_Time} )) & " 23:59:59")

In the output datetime field in skuid shows as 10/28/2015 7:59 PM.

I thought it would show as 10/28/2015 12:59 PM

Does this have something to do with time zones or my formating? Any ideas?

Salesforce date times do take your local time zone into account and adjust accordingly. 

This is more a Salesforce formula question - not really a skuid question though.  Better handled on the success community.