Thursday, August 27, 2020 5:00 AM CT
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HURRICANE LAURA BRIEFING 5:00 AM CT Thursday, August 27, 2020 Prepared by: WFO Memphis, TN What has changed: Laura is now a Category 3 Hurricane. Disclaimer: The information contained within is time-sensitive. Do not use after 10:00am CDT Thursday. NWSMemphis www.weather.gov/Memphis Situation Overview Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ Hurricane Laura made landfall early this morning near Cameron, LA as a strong category 4 hurricane and should gradually decrease in strength as it continues to move inland over the next 24 hours. ▪ The Laura should track north through Louisiana into central Arkansas and bend northeast and move across the area on Friday. ▪ Our impacts locally should start later on today and could last through Saturday afternoon. ▪ Main threats for the Mid-South will be heavy rain that could cause flash flooding and flooding of rivers, gusty winds, and tornadoes are possible. 8/27/2020 5:06 AM www.weather.gov/Memphis Threat Levels Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE For information on specific hazards in this area, please go to https://www.weather.gov/s rh/tropical?office=meg Increasing Threat Increasing Rainfall/ River Wind Tornadoes Flash Flooding Flooding 8/27/2020 5:06 AM www.weather.gov/Memphis Situation Overview Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ Hurricane Laura is now a category 3 hurricane. ▪ Laura will continue to weaken today as it continues to press inland. ▪ Laura will move north into Arkansas early Friday morning and should move across the forecast area Friday. NOTE: Do not focus on the exact track. Impacts can occur well outside the area enclosed by the cone. 8/27/2020 5:06 AM www.weather.gov/Memphis Tropical Storm Force Speed Probabilities Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ With Laura being a large and strong storm, the possibility of tropical storm force winds making it into the forecast area is now between 5-30 percent. ▪ The greatest chances of seeing tropical storm force winds is highest across the Mississippi Delta and portions of southeast Arkansas. ▪ Tropical storm force wind gusts could make it further into the forecast area than the graphic shows. 8/27/2020 5:06 AM www.weather.gov/Memphis Wind Advisory Memphis, TN WEATHER FORECAST OFFICE • A Wind Advisory has been issued for a large portion of the forecast area starting this afternoon and lasting through Friday evening. • Sustained winds of 20 to 30 mph with gusts up to 40 mph will be possible in the advised area starting this afternoon and lasting through Friday evening. 8/27/2020 5:06 AM www.weather.gov/Memphis Inland Flooding Impacts Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ The potential for river flooding exists over a large portion of the Mississippi River Valley. ▪ Flooding rain threat is highly dependent on the evolution of rain bands and overall coverage of rain. Flooding Rain Threat Potential for extreme Potential for major Potential for moderate Potential for localized Little to no potential flooding rain flooding rain flooding rain flooding rain for flooding rain 8/27/2020 5:06 AM www.weather.gov/Memphis Expected Storm Total Rainfall Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE Note: There will likely be locally higher amounts ▪ Rainfall forecast valid this morning through Saturday evening. ▪ Rainfall of 2 to 4 inches is generally expected over the area. However, rainfall amounts could be locally higher depending on the position of rain bands. ▪ Rainfall will be efficient and rainfall rates could be as high as 2 inches per hour ▪ Locally, most rain will occur late tonight through Friday night 8/27/2020 5:06 AM www.weather.gov/Memphis Excessive Rainfall Outlook Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE Excessive Rainfall Outlook Valid Thursday ▪ Portions of the Mid-South will be under a Marginal to Slight Risk of Excessive Rainfall. 8/27/2020 5:06 AM www.weather.gov/Memphis Excessive Rainfall Outlook Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE Excessive Rainfall Outlook Valid Friday • The threat of Excessive Rainfall increases for the area on Friday as the remnants of Laura move directly over the region. • Portions of northwest Tennessee, and the Missouri bootheel will be in a Moderate Risk for excessive rainfall. • A larger portion of the forecast area will be in a Marginal to Slight Risk of excessive rainfall 8/27/2020 5:06 AM www.weather.gov/Memphis Flash Flood Watch Memphis, TN WEATHER FORECAST OFFICE • A Flash Flood Watch has been issued starting this afternoon through Friday night for a large portion of the forecast area. • Heaviest rainfall will be within tropical rain bands that will move across the region. • Rainfall rates up to 2 inches per hour will be possible and could cause flash flooding. 8/27/2020 5:06 AM www.weather.gov/Memphis Tornado Potential Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ Tornadoes will be a threat across the region today. ▪ A Marginal to Slight Risk of severe weather exists for portions of the forecast area. ▪ Tornadoes should be quick moving and short lived if they occur. 8/27/2020 5:06 AM www.weather.gov/Memphis Tornado Potential Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE • The tornado threat continues into Friday. • The threat of tornadoes increases for the area on Friday as the remnants of Laura rotate over the forecast area. Again, if tornadoes do occur they should be fast moving and short lived. • A Slight Risk of severe exists for the area nearly all of the Mid South. 8/27/2020 5:06 AM www.weather.gov/Memphis Key Take-Aways Memphis, TN Hurricane Laura WEATHER FORECAST OFFICE ▪ Hurricane Laura will continue to move inland today. ▪ Impacts across the local area should begin this afternoon. ▪ Heavy rain, gusty winds, and tornadoes will all be threats through Saturday. ▪ The impacts depend on the evolution of the remnants of Laura. Forecast confidence has generally increased in the impacts expected across the area. 8/27/2020 5:06 AM www.weather.gov/Memphis.