Coughing in the middle of the day can be caused by environmental factors, common cold, bronchitis, asthma and so on. 1. Environmental factors: always coughing at noon when the weather is hot, do not rule out the possibility of too hot environment leading to respiratory tract dryness caused by irritating cough. 2. Common cold: common cold will not only cause the patient to cough at noon when the weather is hot, but also at other times of the day. 3. Bronchitis: Acute bronchitis and eosinophilic bronchitis may cause abnormal coughing symptoms. 4. Asthma: Bronchial asthma and cough variant asthma may also cause cough symptoms. There are many reasons that can cause unusual cough symptoms to occur. Individuals who experience unexplained coughing all the time are advised to seek medical attention.