WTUS86 KSGX 210258 HLSSGX CAZ043-048-050-055>058-060>062-065-552-554-211100- Tropical Storm Hilary Local Statement Intermediate Advisory Number 18A National Weather Service San Diego CA EP092023 758 PM PDT Sun Aug 20 2023 This product covers EXTREME SOUTHWESTERN CALIFORNIA **CATASTROPHIC AND LIFE-THREATENING FLOODING LIKELY OVER BAJA CALIFORNIA AND THE SOUTHWESTERN U.S. THROUGH MONDAY** NEW INFORMATION --------------- * CHANGES TO WATCHES AND WARNINGS: - None * CURRENT WATCHES AND WARNINGS: - A Tropical Storm Warning is in effect for Apple and Lucerne Valleys, Coachella Valley, Orange County Coastal Areas, Orange County Inland Areas, Riverside County Mountains, San Bernardino County Mountains, San Bernardino and Riverside County Valleys-The Inland Empire, San Diego County Coastal Areas, San Diego County Deserts, San Diego County Mountains, San Diego County Valleys, San Gorgonio Pass Near Banning, and Santa Ana Mountains and Foothills * STORM INFORMATION: - About 50 miles east of San Mateo Point CA or about 70 miles north-northeast of Mouth of Tijuana River CA - 33.5N 116.7W - Storm Intensity 50 mph - Movement North or 350 degrees at 23 mph SITUATION OVERVIEW ------------------ Tropical Storm Hilary is moving northward through Southern California and should be north of the region as a remnant low by Monday morning. Flash flooding has occurred in some areas and is expected to continue, with rare and dangerous flooding expected across the mountains and deserts into Monday morning. Strong, tropical-storm force winds will continue through tonight, mainly inland on higher terrain. POTENTIAL IMPACTS ----------------- * WIND: Protect against hazardous wind having possible limited impacts across EXTREME SOUTHWESTERN CALIFORNIA. Potential impacts include: - Damage to porches, awnings, carports, sheds, and unanchored mobile homes. Unsecured lightweight objects blown about. - Many large tree limbs broken off. A few trees snapped or uprooted, but with greater numbers in places where trees are shallow rooted, especially in coastal and valley locations that don't typically experience strong winds. Some fences and roadway signs blown over. - A few roads impassable from debris, particularly within urban or heavily wooded places. Hazardous driving conditions on bridges and other elevated roadways. - Scattered power and communications outages. * SURGE: Little to no impacts are anticipated at this time across EXTREME SOUTHWESTERN CALIFORNIA. * FLOODING RAIN: Protect against life-threatening rainfall flooding having possible devastating impacts across Southern California. Potential impacts include: - Extreme rainfall flooding may prompt numerous evacuations and rescues. - Rivers and tributaries may overwhelmingly overflow their banks in many places with deep moving water. Small streams, creeks, canals, arroyos, and ditches may become raging rivers. In mountain areas, deadly runoff may rage down valleys while increasing susceptibility to rockslides and mudslides. Flood control systems and barriers may become stressed. - Flood waters can enter numerous structures within multiple communities, some structures becoming uninhabitable or washed away. Numerous places where flood waters may cover escape routes. Streets and parking lots become rivers of raging water with underpasses submerged. Driving conditions become very dangerous. Numerous road and bridge closures with some weakened or washed out. Protect against life-threatening rainfall flooding having possible extensive impacts across Southern California. * TORNADOES: Little to no impacts are anticipated at this time across EXTREME SOUTHWESTERN CALIFORNIA. PRECAUTIONARY/PREPAREDNESS ACTIONS ---------------------------------- * EVACUATIONS: Listen to local official for recommended preparedness actions, including possible evacuation. If ordered to evacuate, do so immediately. * OTHER PREPAREDNESS INFORMATION: Now is the time to complete all preparations to protect life and property in accordance with your emergency plan. Ensure you are in a safe location before the onset of strong winds or possible flooding. If you are relocating to safe shelter, leave as early as possible. Allow extra time to reach your destination. Many roads and bridges will be closed once strong winds arrive. Check the latest weather forecast before departing and drive with caution. If heading to a community shelter, become familiar with the shelter rules before arrival, especially if you have special needs or have pets. Take essential items with you from your Emergency Supplies Kit. Failure to adequately shelter may result in serious injury or loss of life. Always heed the advice of local officials and comply with any orders that are issued. Remember, during the storm 9 1 1 Emergency Services may not be able to immediately respond if conditions are unsafe. This should be a big factor in your decision making. Keep cell phones well charged. Cell phone chargers for automobiles can be helpful, but be aware of your risk for deadly carbon monoxide poisoning if your car is left idling in a garage or other poorly ventilated area. It is important to remain calm, informed, and focused during an emergency. Be patient and helpful with those you encounter. If you are a visitor, be sure to know the name of the city or town in which you are staying and the name of the county or parish in which it resides. Listen for these locations in local news updates. Pay attention for instructions from local authorities. Storm surge is the leading killer associated with tropical storms and hurricanes! Make sure you are in a safe area away from the surge zone. Even if you are not in a surge-prone area, you could find yourself cutoff by flood waters during and after the storm. Heed evacuation orders issued by the local authorities. Rapidly rising flood waters are deadly. If you are in a flood-prone area, consider moving to higher ground. Never drive through a flooded roadway. Remember, turn around don't drown! If a Tornado Warning is issued for your area, be ready to shelter quickly, preferably away from windows and in an interior room not prone to flooding. If driving, scan the roadside for quick shelter options. If in a place that is vulnerable to high wind, such as near large trees, a manufactured home, upper floors of a high-rise building, or on a boat, consider moving to a safer shelter before the onset of strong winds or flooding. Closely monitor weather.gov, NOAA Weather radio or local news outlets for official storm information. Be ready to adapt to possible changes to the forecast. Ensure you have multiple ways to receive weather warnings. * ADDITIONAL SOURCES OF INFORMATION: - For information on appropriate preparations see ready.gov - For information on creating an emergency plan see getagameplan.org - For additional disaster preparedness information see redcross.org NEXT UPDATE ----------- The next local statement will be issued by the National Weather Service in San Diego CA around 11 PM PDT, or sooner if conditions warrant. $$ 12