Use value like ISO_WEEK but start week on sunday

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SQL

SQL-Server

I am trying to get my calendar dimension to properly calculate the weeks of the year which ISO_week seemed to be a solution yet I am in the USA and our weeks start on Sunday. Is there a way to get the weeks to start on Sundays while still having end/start of years being in proper weeks like how ISO_WEEK calculates it? My current Add to dictionary starts on Sundays yet has a 53rd week every year because I don't have an indepth formula. Currently I'm using

DATEPART(WW, @CurrentDate) AS week_of_year,

Background information on @CurrentDate would be

DECLARE @StartDate DATETIME = '01/04/2010' --Starting value of Date Range
DECLARE @EndDate DATETIME = '01/01/2050' --End Value of Date Range
DECLARE @CurrentDate AS DATETIME = @StartDate
SET @CurrentMonth = DATEPART(MM, @CurrentDate)
SET @CurrentYear = DATEPART(YY, @CurrentDate)
SET @CurrentQuarter = DATEPART(QQ, @CurrentDate)

What I have tried:

Currently for ISOweek I have:

[isoweek] AS DATEPART(ISO_WEEK, [date_day]),

Date_day is just date
I have also tried

[iso_week_of_year] TINYINT NULL,
iso_week_of_year = CONVERT(TINYINT, isoweek),

These just return the weeks starting on Monday as expected.