His accurate weather reports helped innumerable mountaineers to finalize their schedule and to avoid unforeseen circumstances. He worked for Simone Moro (who called Carl the forecast "guru" of Innsbruck), Artur Hajzer, Krzysztof Wielicki, Gerlinde Kaltenbrunner (also when she climbed the North pillar of K2 with Darek Załuski), Ralf Dujmovits, and Ueli Steck.

Karl Gabl started as a climber and completed his training as a mountain guide. He successfully climbed several peaks in the Alps and skied from Noshaq, the highest mountain in Afghanistan (7485m). At the same time he was fulfilling his passion, Gabl graduated from the University of Innsbruck and acquired his Ph.D. in Meteorology and in Philosophy. He was elected as the head of regional office of the Central Institute for Meteorology and Geodynamics in Innsbruck, where he stayed until his retirement. He still provides 50-60 expeditions per year with free forecasts. Karl Gabl wrote a book titled "Mountain Weather" (Bergwetter, Bruckmann Verlag, Munich) and memoirs "Karl Gabl, I have seen the clouds from both sides", Tyrolia Verlag, Innsbruck.