Tropical Cyclone Local Statement: San Diego County Coastal Areas; San Diego County Inland Valleys; San Diego County Mountains; San Diego County Deserts

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Tropical Cyclone Local Statement — San Diego County Coastal Areas; San Diego County Inland Valleys; San Diego County Mountains; San Diego County Deserts Severity: Moderate. Certainty: Likely. HLSSGX This product covers EXTREME SOUTHWESTERN CALIFORNIA **Impacts from Tropical Storm Rachel Expected in San Diego County Late Tonight through Early Sunday Afternoon** NEW INFORMATION --------------- * CHANGES TO WATCHES AND WARNINGS: - None * 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 440 miles south of San Mateo Point CA or about 390 miles south of Mouth of Tijuana River CA - 27.0N 118.3W - Storm Intensity 65 mph - Movement North-northeast or 25 degrees at 30 mph SITUATION OVERVIEW ------------------ Tropical Storm Rachel is currently about 400 miles south of San Diego, moving north-northeast towards Northern Baja at about 30 mph. Rachel is expected to make landfall south of the US/Mexico Border tonight. Tropical storm level impacts will likely affect San Diego County. A Tropical Storm Watch is in effect for all of San Diego County. The main concerns with Tropical Storm Rachel are coastal flooding, wind, and periods of heavy rain which could lead to localized flooding and flash flooding. The majority of impacts from the tropical storm are expected late tonight through early Sunday afternoon. South swell from Tropical Storm Rachel will arrive on Sunday. The combination of south and northwest swells, increased onshore winds, and high tides over 7 feet will maintain a threat of coastal flooding and beach erosion along area beaches. Surf on Sunday is currently expected to peak at 6 to 9 feet, decreasing to 3 to 6 feet for Monday and Tuesday. Confidence in impactful coastal flooding is high, with significant coastal flooding and beach erosion likely. Widespread rain is expected on Sunday from Tropical Storm Rachel. There is expected to be a gradient in rainfall amounts with the higher amounts on the southeastern side of the storm. Confidence is high that the heaviest rain will occur over San Diego County mountains and deserts. Peak rainfall rates of 0.50 to 0.60 inches are possible for the coast and valleys, 0.50 to 0.70 inches per hour possible for the deserts, and 0.70 to 1 inch per hour for the mountains. Current forecast has rainfall totals of 0.50 to 1.25 inches for the coast, valleys, and deserts and 1 to 2.5 inches for the mountains. Areas of flash and urban flooding are probable, especially where the maximum rainfall rates occur. The San Diego River at Fashion Valley is currently forecast to peak at 8.0 feet (action/monitor stage) just before noon on Sunday. Those with interests near the San Diego River should continue to monitor the forecast. Increased winds are expected with the onset and passage of Tropical Storm Rachel. Sustained winds of 39+ mph are expected on the southeast side of the storm. Based on the current track, more southern and eastern parts of San Diego County are most likely to see winds of this magnitude. Regardless, strong sustained winds and wind gusts can be expected on Sunday. Winds will likely be enhanced by local terrain with gusts 40 to 55 mph on the desert slopes of the mountains and into the deserts. Local gusts up to 60 mph possible on mountain ridges and in passes and canyons. Winds are expected to remain elevated in Rachel's wake with continued strong gusts on the desert mountain slopes into the deserts through Monday morning. POTENTIAL IMPACTS ----------------- * OTHER COASTAL HAZARDS: High tides over 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. Significant coastal flooding and beach erosion is likely. * FLOODING RAIN: Prepare for life-threatening rainfall flooding having possible extensive impacts across San Diego County. Potential impacts include: - Major rainfall flooding may prompt many evacuations and rescues. - Rivers and tributaries may rapidly overflow their banks in multiple places. Small streams, creeks, canals, arroyos, and ditches may become dangerous rivers. In mountain areas, destructive runoff may run quickly down valleys while increasing susceptibility to rockslides and mudslides. Flood control systems and barriers may become stressed. - Flood waters can enter many structures within multiple communities, some structures becoming uninhabitable or washed away. Many places where flood waters may cover escape routes. Streets and parking lots become rivers of moving water with underpasses submerged. Driving conditions become dangerous. Many road and bridge closures with some weakened or washed out. Prepare for dangerous rainfall flooding having possible significant impacts across San Diego County. * WIND: Prepare for hazardous wind having possible limited impacts across EXTREME SOUTHWESTERN CALIFORNIA. 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. 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, in a valley, or near a river, plan to move to safe shelter on higher ground. Always heed the advice of local officials and comply with orders that are issued. Do not needlessly jeopardize your life or the lives of others. 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 8 PM PDT, or sooner if conditions warrant.