Help with Skybox Fading

Okay, what I want to do is fade from a night skybox to a day skybox upon the sun’s rotation becoming in-between 0 and 90. I have done this fine for when it fades from a day to a night skybox, but for some reason when I want to change from night to day it just pops instantly in, without fading. Could I please have some help as to solving this issue? I am using the Skybox Blend shader.
(The top if statement is day to night, the bottom one is night to day; the one I need help with.)

if(sunRotation <= 360 && sunRotation >= 270){
	var blendAmount : float = timeOfDay * 0.5;
	RenderSettings.skybox.SetFloat("_Blend", blendAmount);
if(sunRotation >= 0 && sunRotation <= 90){
	var blendAmount1 : float = timeOfDay * 0.5;
	if(blendAmount1 < 0){
		blendAmount1 = 0;
	RenderSettings.skybox.SetFloat("_Blend", -blendAmount1);

Maybe you could use Mathf.Sin to adjust the value?

function SkyboxBlend(var degrees : float) : float
    var radians = degrees * Mathf.Deg2Rad;
    var sin = Mathf.Sin(radians);
    return Mathf.Clamp01(sin);

function UpdateSkybox()
    RenderSettings.skybox.SetFloat("_Blend", SkyboxBlend(sunRotation));