Tweening not working properly, help?

I am trying to tween the lighting's ColorShift_Top seamlessly while also making time go by. I made this script:

local Glows = {
	["Morning_Glow"] = Color3.fromRGB(255, 140, 35),
	["Noon_Glow"] = Color3.fromRGB(255, 255, 125),
	["Evening_Glow"] = Color3.fromRGB(175, 45, 5),
	["Night_Glow"] = Color3.fromRGB(15, 20, 75)
}

local function GetGlow()
	local CT = Lighting.ClockTime
	
	if CT > 6 and CT <= 8 then
		return Glows.Morning_Glow
	elseif CT > 8 and CT <= 16 then
		return Glows.Noon_Glow
	elseif CT > 16 and CT <= 18 then
		return Glows.Evening_Glow
	else
		return(Glows.Night_Glow)
	end
end

while true do
	Lighting.ClockTime = Lighting.ClockTime + increment
	
	local Ambient = Lighting.ColorShift_Top
	local NewAmbient = GetGlow()
	
	if Ambient == NewAmbient then
		Lighting.ColorShift_Top = NewAmbient
	else
		local newTween = TS:Create(Lighting, TI, {ColorShift_Top = NewAmbient})
		newTween:Play()
	end
	wait()
end

(Some parts not included.)

But when it tweens, it is vey slow. I know this is due to tweens overlapping, but how can I fix this? I need the tween to play in the "Background," with the rest of the script still running.

EDIT: The tweeninfo is:

TweenInfo.new(1.5, Enum.EasingStyle.Quad, Enum.EasingDirection.In)

Ok, here's how I fixed it. I first defined the colorTween as a filler tween in the start of the script:

local colorTween = TS:Create(Lighting, TI, {ColorShift_Top = Color3.fromRGB(0,0,0)})

This does nothing until the ambient changes, at which point it would check the playback state:

if Ambient == NewAmbient then
	Lighting.ColorShift_Top = NewAmbient
else
	if colorTween.PlaybackState ~= Enum.PlaybackState.Playing then
		colorTween = TS:Create(Lighting, TI, {ColorShift_Top = NewAmbient})
		colorTween:Play()
	end
end

This prevents it from running while it's already running.