High Desert monsoon thunderstorm season Published Aug. 11, 2015 By Gary Davis 412th Operations Support Squadron Staff Meteorologist EDWARDS AIR FORCE BASE, Calif. -- With the start of the summer season at Edwards, the threat of monsoon thunderstorms becomes a major concern for the 412th Operations Support Squadron Weather Flight. During this period, the wind flow in Southern California can shift to a southeast to southerly directional flow. As a result, tropical moisture flows in from the Gulf of Mexico or the Pacific Ocean (near Baja) into Southern California. This tropical moisture combined with our intense desert heat and mountainous terrain, aids in producing scattered afternoon and evening thunderstorm activity across the Antelope Valley. When monsoon thunderstorm activity is forecast to occur, the 25th Operational Weather Squadron based out of Davis-Monthan Air Force Base, Arizona, will issue weather watches and warnings for Edwards AFB. A Weather Watch is a special notice provided to supported agencies that alerts them of the potential for hazardous weather conditions of such intensity as to pose a threat to life and/or property. A Weather Warning on the other hand, is issued when a hazardous weather event is occurring, is imminent, or has a very high probability of occurring. A weather warning is also used to alert supported agencies of weather conditions that pose a threat to life and/or property. Associated with monsoonal thunderstorm activity are flash floods. Flash floods are the number one cause of weather related deaths in the United States with lightning being the second cause of death. On average, 65 people are killed by lightning every year with well over 400 seriously injured. Flash floods on the other hand, account for more than 90 fatalities each year. Hail is also a real possibility with monsoonal thunderstorms along with "dry microbursts," which are very strong and damaging surface winds associated with collapsing thunderstorms. Dry microbursts can also produce dust storms also known as "haboobs" that occasionally occur during monsoon season. When dangerous weather approaches, keep the following safety tips in mind: 1. Plan: Know the latest weather forecast before planning outdoor activities. 2. Monitor the weather: Look for signs of developing thunderstorm activity such as darkening skies, flashes of lightning, or increasing wind. 3. Safe Places: Large, fully enclosed buildings with wiring and plumbing provide good lightning protection. Vehicles with solid metals roofs and solid metal sides give some protection. 4. Indoor Safety: Don't use corded telephones. Keep away from electrical appliances and wiring. Stay away from plumbing - don't take a bath or shower and unplug sensitive electronics. 5. Outdoor Safety: Avoid open areas (golf courses, sports fields and beaches), water (swimming, boating and fishing) and tall objects. If you are stuck in a large open area during a thunderstorm, crouch low to the ground. If you feel the hair rise up on your head or neck like static electricity, drop to the ground immediately but most importantly do not stand up. Do not go under trees and allow time to get to safety. Do not use open structures like picnic pavilions and rain shelters, and in low lying natural drainage areas, be on the lookout for flash floods. 6. First Aid: If someone is struck by lightning, start CPR immediately if they are not breathing. Have someone call 911 from a land line or call 661-277-3340 from a cell phone if on EAFB proper. Outside of Edwards, dial 911 from a cell phone. Monsoon season at Edwards typically begins in July and ends by late September. It is important for everyone to take the appropriate safety precautions when thunderstorms develop and when the threat for lightning persists. A final factor to consider, especially on days when the potential for thunderstorms exist, is heat stress. High temperatures alone can cause heat stress, but the added element of humidity can further increase the likelihood for heat stress to occur. More information on lightning safety is available on the web at: http://www.lightningsafety.noaa.gov/.