Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 309 AM EDT Tue Aug 29 2017 Valid 12Z Tue Aug 29 2017 - 12Z Thu Aug 31 2017 ...An additional 6 to 12 inches of rainfall likely over flash flood ravaged areas of the upper Texas coast... ...Isolated tornadoes are possible from the upper Texas coast into coastal Louisiana/Mississippi on Tuesday... ...Heavy rainfall in response to a potential tropical disturbance to impact the Outer Banks into the Delmarva Peninsula... ...More record heat expected across the western United States... Tropical Storm Harvey continues to wreak havoc over southeastern Texas into sections of southern Louisiana. Extreme rainfall totals have accompanied this system with up to 3 feet of precipitation having already fallen over areas of southeast Texas. With the forecast indicating another 6 to 12 inches likely over this region, some locations may be reporting nearly 50 inches when it is all said and done. Suffice to say, any additional heavy rainfall will only exacerbate the issues and make relief efforts challenging. Over the next couple of days, Harvey is expected to gradually nose back toward the coast making another landfall near Port Arthur, Texas by early Wednesday morning. Its forward speed is expected to pick up as an upper trough helps accelerate it toward the Ozarks. However, until it moves sufficiently inland, flash flooding will remain a concern from southeast Texas eastward into southern Louisiana/Mississippi with an accompanying threat for isolated tornadoes. For the latest information on the flash flood concerns ahead, please view the excessive rainfall discussion at Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php While Harvey continues to dominate the national news, another potential tropical system is in the works along the Carolina coast. Recent forecasts indicate it could attain tropical cyclone status later today although this remains to be seen. Regardless, expect heavy rainfall to impact areas from the North Carolina Outer Banks northward into the Delmarva Peninsula region. 2 to 4 inches of precipitation is forecast over this area with an accompanying risk for flash flooding. The track of this cyclone will take it farther offshore with gusty winds and rough seas remaining in its wake. Additionally, rather cool conditions for late August will prevail along the Eastern Seaboard with forecast temperature anomalies around 10 to 15 degrees below average. Even some highs in the 60s are likely over the Mid-Atlantic and lower New England on Tuesday. Across the western United States, persistent upper ridging overhead will help enforce well above normal temperatures. A number of daily temperature records are likely to be broken anywhere from California northward into the Central Great Basin and interior Pacific Northwest as highs will be 10 to 20 degrees above average. Current forecasts suggest 100 degree plus readings extending out of the Desert Southwest into the interior central valleys of California. Rubin-Oster Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php