diff --git a/app/app.py b/app/app.py
index f5e736e304075e21b5551fd0cdccb07c8b3f4f32..6059102aefac6976992410022bb2812c3260745f 100644
--- a/app/app.py
+++ b/app/app.py
@@ -7,6 +7,7 @@ from ipmd_weatherdata import WeatherData, weatherdata_utils
 
 app = Flask(__name__)
 
+SITE_ROOT = os.path.dirname(os.path.realpath(__file__))
 
 @app.route("/")
 def index():
@@ -27,7 +28,7 @@ def get_weather_data():
     # Input check
     if longitude is None or latitude is None:
         return "BAD REQUEST: longitude (%s) and/or latitude (%s) is not set" % (longitude, latitude), 403
-    wd_file = open("./data_files/2021_apelsvoll_redigert.json")
+    wd_file = open(SITE_ROOT + "/data_files/2021_apelsvoll_redigert.json")
     weather_data = WeatherData(**json.load(wd_file))
     wd_file.close()