They can start as early as the first week of June or as late as August and last until mid August or early September. They are of little concern for expeditions except if they are accompanied with lightning. We deal with this situation by not being on the ridges when there is the possibility of lightning. This has not been a problem. A typical day during the monsoons has the sun and clear skies in the morning with clouds gathering during the day with a brief shower followed by clearing skies, and no clouds during the night.
Snow is possible in the mountains in the early and late portions of the season.
Usually these are light snow showers and melt rapidly. We avoid extremes by planning the expeditions with the weather in mind, moving operations up into the higher mountains with the advancing warm weather and moving operations in the opposite direction as Fall descends from the peaks. The Northern New Mexico Rockies get the weather typical of mountains . Because of our lower latitude, we enjoy some benefits over the mountains in the states to the north. Our snow melts earlier in the spring and arrives later in the fall.