A trough tends to have increased cloud cover near it, the cloud cover being extended ahead of it when the trough is moving.
उनी शान्त तलाउमा ढुंगा हानेर तरंगित पैदा गर्दै केन्द्रविन्दुमा आफै रहेको सन्देश प्रवाह गर्छन् ।