Respected Johan, hi I evaluated your query thoroughly. *This is related to Bronchospasm induced by the atmospheric humidity in which your lung bronchi & alveoli shrink in response to give you above said all symptoms in presence of normal EKG, X-ray & blood tests. *In our clinic we evaluate the patient in terms of Pulmonary function test to evaluate for the Lung Capacity & other parameters to find the exact problem along with necessary molecules to eliminate the issue fairly. *Till then my suggestions for you are : - avoid exposure to excess cold / pollen containing atmospheres - maintain your hydration by plenty of liquids - have nutritious diet with proteins, iron , fiber , vitamins , minerals , anti- oxidants to combat against any external atmospheric insult - apart from your walking, jogging, do regularly Deep Breathing Exercises with YOGA for 30 min . daily without failure - protect your chest properly when going out in cold / snow fall - avoid smoking / alcohol / any abuse substances if used - when resting prefer semi-reclining position ( keeping back at 30-40 degree angle ) - have adequate sound sleep of 8 hours - avoid stress / anxiety - keep your Haemoglobin , BP , Blood sugar, Cholesterol levels , weight under control - can evaluate yourself at home your lung capacity by simple measure of Spirometer in which you will get exercise of the lung with daily evaluation of results in terms of improvement of lung functioning - tincture benzoin / Karvol capsules inhalations in leukwarm water with towel covered over head with deep breathings for 10-10 min. 3 times a day helps a lot. - specific molecules as Bronchodilators may be required in selected cases for which you have to consult your Physician for prescription. Hope this clears your query. Thanks for using Health Care Magic & giving us opportunity to serve you. Wishing you a very happy healthy life ahead. Feel free to ask any further health related queries in future. Regards dear take care.