Tropical Cyclone Local Statement for San Diego County Coastal Areas; San Diego County Inland Valleys; San Diego County Mountains +1 more

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HLSSGX This product covers EXTREME SOUTHWESTERN CALIFORNIA **Tropical Storm Rachel Will Bring Coastal Flooding, Wind, and Rain to Portions of Southern California Sunday** NEW INFORMATION --------------- * CHANGES TO WATCHES AND WARNINGS: A Tropical Storm Watch has been issued for San Diego County Coastal Areas, San Diego County Deserts, San Diego County Mountains, and San Diego County Valleys * CURRENT WATCHES AND WARNINGS: A Tropical Storm Watch is in effect for San Diego County Coastal Areas, San Diego County Deserts, San Diego County Mountains, and San Diego County Valleys * STORM INFORMATION: About 840 miles south-southwest of San Mateo Point CA or about 810 miles southwest of Mouth of Tijuana River CA 22.8N 124.6W Storm Intensity 50 mph Movement Northeast or 55 degrees at 5 mph SITUATION OVERVIEW ------------------ Tropical Storm Rachel is moving towards Northern Baja. Rachel is expected to make landfall somewhere near the US/Mexico Border. While there remains some uncertainty in the track, the current trend in the guidance increases the likelihood that Tropical Storm level impacts may reach San Diego County on Sunday. Tropical Storm Watch has been issued for San Diego County. The main concerns with Tropical Storm Rachel are coastal flooding, wind, and periods of heavy rain. South swell from Tropical Storm Rachel will arrive on Sunday. The combination of the swell along with wind waves and continued morning high tides near 7 feet will maintain a threat of coastal flooding and beach erosion along beaches in San Diego County. Surf on Sunday is currently expected to be 5 to 7 feet with local sets to 9 feet, decreasing to 3-6 feet for Monday and Tuesday. Confidence in impactful coastal flooding is high. Widespread rain is expected on Sunday from Tropical Storm Rachel. There is expected to be a sharp gradient in rainfall amounts with the higher amounts on the southeastern side of the storm. There still remains some uncertainty in the track, but a continued northern shift would increase potential for heavy rain across the county with a southern shift making it more localized. We have the highest confidence that the heaviest rain will occur over San Diego county mountains and deserts. The most likely scenario, accounting for around 50% of solutions, brings San Diego coast, valleys, and deserts a soaking rain between 0.25-1" Sunday with 1-2 inches in the mountains. Assuming the low tracks close enough to the mountains, easterly flow over the desert slopes could yield high rates (>0.5/hr) and totals (1-2 inches). The higher end case brings 1-2" over the coast, valleys, deserts and 2-4" over the mountains, which could result in more numerous impacts. Increased winds are expected with the onset and passage of TS Rachel. Sustained winds of 39+ mph are expected on the southeast side of the storm. If the track continues to move further north, that would put more of San Diego county in a position to see winds of that magnitude. Based on the current track, more southern parts of the county are most likely to see winds of this magnitude. Regardless, stronger than normal sustained winds and wind gusts can be expected on Sunday. Locations north of San Diego County are expected to also see impacts from coastal flooding, the potential for heavy rain, and elevated winds. POTENTIAL IMPACTS ----------------- * WIND: Prepare for hazardous wind having possible limited impacts across San Diego County. Potential impacts in this area 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. Elsewhere across EXTREME SOUTHWESTERN CALIFORNIA, little to no impact is anticipated. * FLOODING RAIN: Prepare for dangerous rainfall flooding having possible significant impacts across San Diego County. Potential impacts include: Heavy rainfall flooding may prompt several evacuations and rescues, especially in and below recently burned areas. Rivers may quickly become swollen with swifter currents and overspill their banks in a few places, especially in usually vulnerable spots. Small streams, creeks, arroyos, and ditches overflow. Flood waters can enter some structures or weaken foundations. Several places may experience expanded areas of rapid inundation at underpasses, low-lying spots, and poor drainage areas. Some streets and parking lots take on moving water as storm drains overflow. Driving conditions become hazardous. Some road closures. Prepare for locally hazardous rainfall flooding having possible limited impacts across San Diego County. * OTHER COASTAL HAZARDS: High tides reaching 7 ft, combined with high surf and gusty onshore winds will increase the threat for coastal flooding across area beaches. Additionally surf of 6 to 9 ft will create dangerous swimming conditions. PRECAUTIONARY/PREPAREDNESS ACTIONS ---------------------------------- * EVACUATIONS: Follow the advice of local officials. * OTHER PREPAREDNESS INFORMATION: If you live in a place particularly vulnerable to flooding, such as near the ocean, in a low-lying or poor drainage area, or in a valley, plan to move to safe shelter on higher ground. Now is the time to check your emergency plan and emergency supplies kit and take necessary actions to protect your family and secure your home or business. Always heed the advice of local officials and comply with orders that are issued. Closely monitor weather.gov, NOAA Weather Radio and local news outlets for official storm information. Listen for possible changes to the forecast. * 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 2 PM PDT, or sooner if conditions warrant.