The weather looked clear as we made it up to the summit of Kat Carson. However, moisture builds over the San Juan range and then builds into storms over the warmer San Luis Valley. Our view of the San Luis Valley and the impeding storm was obstructed by Columbia Point's rocky east face. At 2:00 pm, and without warning, the sky opened up and thunder pounded against the mountain walls around us. We took shelter in a crevasse on Kat Carson's northern ridge for 45 minutes. The view of the storm was amazing and we felt protected from the lightning.