Custom color scale for scatter_mapbox failing when color value is only zero

When the value I have set to “color” from my dataframe for the px.scatter_mapbox is only equal to zero for ALL points, then the scales goes weird and sets its minimum below 0. I have a custom scale set as follows:

custom_colorscale = [
[0, ‘rgb(20, 20, 20)’],
[0.5, ‘rgb(4, 55, 242)’],
[1, ‘rgb(205, 102, 0)’],

I also attempted to set a minimum value, but it doesnt’ fix the issue.

coloraxis=dict(
colorscale=custom_colorscale,
cmin=0, # Set the minimum value for the color scale
colorbar=dict(title=“Snowfall (inches)”) # Set the color bar title

Thoughts on how to keep the scale min to zero?

Thanks,
Eric