Every Azimuth equation I have been able to locate so far depends on inputting a time, and I do not want to have to brute force the solution by simply trying all of the times. (See below for standard equations.)
My use case doesn't require great precision, within a few degrees is fine. So, ideally I'm looking for equation(s) that take only latitude (and possibly longitude?) as input and output max and/or min azimuth angles for that location. Also, I'm only going to care about years within a century of now so I don't believe that the year to year variation will matter given my precision requirements, but if I'm wrong I'm happy to provide the current year as well.
Standard Solar Equations Based on NOAA's Solar Calculator
Note: The sunrise and sunset results are theoretically accurate to within a minute
for locations between +/- 72° latitude, and within 10 minutes outside of those latitudes.
However, due to variations in atmospheric composition, temperature, pressure and conditions,
observed values may vary from calculations.
...
Please note that calculations in the spreadsheets are only valid for dates between 1901 and 2099,
due to an approximation used in the Julian Day calculation."
$\Xi = $Latitude (+ to N)
$\Phi = $Longitude (+ to E)
$\omega = $Time Zone (+ to E)
$d = $Date
$\tau = $Time (hrs past local midnight)
$\upsilon = $Julian Day = $d + 2415018.5 + \tau - \frac{\omega}{24}$
$\sigma = $Julian Century = $\frac{\upsilon - 2451545}{36525}$
$\rho = $Geom Mean Long Sun (deg) = $\left(280.46646 + \sigma \left(36000.76983 + 0.0003032\sigma\right)\right) \bmod 360$
$\xi = $Geom Mean Anom Sun (deg) = $357.52911 + \sigma\left(35999.05029 - 0.0001537\sigma\right)$
$\mu = $Eccent Earth Orbit = $0.016708634 - \sigma\left(0.000042037 + 0.0000001267\sigma\right)$
$\lambda = $Sun Eq of Ctr = $\sin\left(\xi^{rad}\right)\left(1.914602 - \sigma\left(0.004817+0.000014\sigma\right)\right) + \sin\left(2\xi^{rad}\right)\left(0.019993 - 0.000101\sigma\right) + 0.000289\sin\left(3\xi^{rad}\right)$
$\kappa = $Sun True Long (deg) = $\rho + \lambda$
$\iota = $Sun True Anom (deg) = $\xi + \lambda$
$\theta = $Sun Rad Vector (AUs) = $\frac{1.000001018\left(1 - \mu^2\right)}{1 + \mu\cos\left(\iota^{rad}\right)}$
$\eta = $Sun App Long (deg) = $\kappa - 0.00569 - 0.00478\sin\left(\left(125.04-1934.136\sigma\right)^{rad}\right)$
$\zeta = $Mean Obliq Ecliptic (deg) = $23 + \frac{26 + \frac{21.448 - \sigma\left(46.815+\sigma\left(0.00059 - \sigma0.001813\right)\right)}{60}}{60}$
$\epsilon = $Obliq Corr (deg) = $\zeta + 0.00256\cos\left(\left(125.04-1934.136\sigma\right)^{rad}\right)$
$\delta = $Sun Declin (deg) = $\left(\arcsin\left(\sin\left(\epsilon^{rad}\right)\sin\left(\eta^{rad}\right)\right)\right)^o$
$y = $var y = $\tan\left(\left(\frac{\epsilon}{2}\right)^{rad}\right)^2$
$\Gamma = $Eq of Time (minutes) = $4\left(y\sin\left(2\rho^{rad}\right)-2\mu\sin\left(\xi^{rad}\right)+4\mu y\sin\left(\xi^{rad}\right)\cos\left(2\rho^{rad}\right)-0.5y^2\sin\left(4\rho^{rad}\right)-1.25\mu^2\sin\left(2\xi^{rad}\right)\right)^o$
$\gamma = $True Solar Time (min) = $\left(1440\tau + \Gamma + 4\Phi - 60\omega\right) \bmod 1440$
$\beta = $Hour Angle (deg) = $if\left(\frac{\gamma}{4}<0\right) \{\\ \frac{\gamma}{4}+180\\ \} else \{\\ \frac{\gamma}{4}-180\\ \}$
$\Omega = $Solar Zenith Angle (deg) = $\left(\arccos\left(\sin\left(\Xi^{rad}\right)\sin\left(\delta^{rad}\right)+\cos\left(\Xi^{rad}\right)\cos\left(\delta^{rad}\right)\cos\left(\beta^{rad}\right)\right)\right)^o$
$\alpha = $Solar Azimuth Angle (deg cw from N) = $if\left(\beta>0\right) \{\\ \left(\arccos\left(\frac{\sin\left(\Xi^{rad}\right)\cos\left(\Omega^{rad}\right)-\sin\left(\delta^{rad}\right)}{\cos\left(\Xi^{rad}\right)\sin\left(\Omega^{rad}\right)}\right)^o+180\right) \bmod 360\\ \} else \{\\ \left(540-\arccos\left(\frac{\sin\left(\Xi^{rad}\right)\cos\left(\Omega^{rad}\right)-\sin\left(\delta^{rad}\right)}{\cos\left(\Xi^{rad}\right)\sin\left(\Omega^{rad}\right)}\right)^o\right) \bmod 360\\ \}$