'Gloomy' in the Bible

“And whenever you are fasting, do not look gloomy like the hypocrites, for they put on a sad and dismal face [like actors, discoloring their faces with ashes or dirt] so that their fasting may be seen by men. I assure you and most solemnly say to you, they [already] have their reward in full.

And in the morning, ‘It will be stormy today, for the sky is red and has a threatening look.’ You know how to interpret the appearance of the sky, but cannot interpret the signs of the times?