The Importance Of Final Year Results In US PhD admissions How important are final year ( more especially final semester ) results in PhD admissions?

I am on MEng course in the UK where final year results are usually released mid to late July, and I intend on applying to US universities, now when reading on the application procedures at many universities I noticed that the application deadline for a lot of US engineering PhD programs seems to be from late November to late January, with admission decisions usually being made around April.So I am curious to know how important final year/semester results are in a PhD application.
Admissions to US graduate programs are generally conditional on final-semester grades. That is, you are required to pass your classes, and in general maintain a reasonable GPA in them. Developing a case of "senioritis" and getting D's on everything could have an effect on your admissions offers. (Whether or not it will depends on the department and the school.)

However, the grades earned in the final semester do not influence the decision whether or not to accept you in the first place; that is determined by your grades up through the end of the first semester of your final year (or the last semester of your penultimate year, if the grades aren't available by mid-year).