SUMMARY OF 400 PM CDT
LOCATION…29.3N 93.2W
ABOUT 35 MI…55 KM S OF CAMERON LOUISIANA
MAXIMUM SUSTAINED WINDS…105 MPH…165 KM/H
PRESENT MOVEMENT…NNE OR 15 DEGREES AT 14 MPH…22 KM/H
MINIMUM CENTRAL PRESSURE…966 MB…28.53 INCHES
FORECAST POSITIONS AND MAX WINDS
INIT 09/2100Z 29.3N 93.2W 90 KT 105 MPH
12H 10/0600Z 31.1N 92.5W 60 KT 70 MPH…INLAND
24H 10/1800Z 33.1N 91.0W 35 KT 40 MPH…INLAND
36H 11/0600Z 34.4N 89.2W 30 KT 35 MPH…INLAND
48H 11/1800Z 35.9N 87.1W 25 KT 30 MPH…INLAND
60H 12/0600Z 37.6N 84.8W 20 KT 25 MPH…POST-TROP/REMNT LOW
72H 12/1800Z…DISSIPATED
KEY MESSAGES
1. Life-threatening storm surge is occurring and will continue near and east of where Delta makes landfall this evening, and a Storm Surge Warning is in effect from High Island, Texas, to the Mouth of the Pearl River, Louisiana. The highest inundation of 7 to 11 feet is expected somewhere between Rockefeller Wildlife Refuge and Morgan City, Louisiana.
2. Hurricane-force winds are expected this afternoon and evening within portions of the Hurricane Warning area, especially along the coast of southwest Louisiana. Hurricane-force winds will also spread inland across portions of southern Louisiana near the path of Deltas center this evening and tonight.
3. Heavy rainfall will lead to significant flash flooding and minor to major river flooding in parts of Louisiana today and Saturday. Additional flooding is expected across portions of the central Gulf Coast into the Lower Mississippi Valley.
OUTLOOK
At 400 PM CDT (2100 UTC), the center of Hurricane Delta was located near latitude 29.3 North, longitude 93.2 West. Delta is moving toward the north-northeast near 14 mph (22 km/h), and this motion is expected to continue through Saturday morning. A motion toward the northeast is then expected through Sunday night. On the forecast track, the center of Delta should make landfall along the coast of southwestern Louisiana during the next few hours, and then move across central and northeastern Louisiana tonight and Saturday morning. After that time, the system is forecast to moves across northern Mississippi into the Tennessee Valley.
Maximum sustained winds are near 105 mph (165 km/h) with higher gusts. Some weakening is possible before landfall, with rapid weakening expected after landfall. Delta is forecast to weaken to a tropical storm tonight and to a tropical depression on Saturday.
Hurricane-force winds extend outward up to 40 miles (65 km) from the center and tropical-storm-force winds extend outward up to 160 miles (260 km). The Texas Coastal Ocean Observation Network station at Texas Point recently reported sustained winds of 62 mph (100 km/h) and a wind gust of 78 mph (126 km/h). The National Ocean Service station at Calcasieu Pass, Louisiana, recently reported sustained winds of 53 mph (85 km/h) and a wind gust of 64 mph (104 km/h).
The estimated minimum central pressure is 966 mb (28.53 inches). The National Ocean Service station at Calcasieu Pass recently reported a pressure of 983.8 mb (29.05 inches).
HAZARDS AFFECTING LAND
STORM SURGE: The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide…
Rockefeller Wildlife Refuge, LA to Morgan City, LA including Vermilion Bay…7-11 ft
Holly Beach, LA to Rockefeller Wildlife Refuge, LA…5-8 ft
Morgan City, LA to Port Fourchon, LA…4-6 ft
Sabine Pass to Holly Beach, LA…3-5 ft
Calcasieu Lake…2-4 ft
High Island, TX to Sabine Pass…2-4 ft
Port Fourchon, LA to the Mouth of the Pearl River…2-4 ft
Lake Borgne…2-4 ft
Lake Pontchartrain and Lake Maurepas…1-3 ft
Mouth of the Pearl River, LA to the AL/FL border including Mobile Bay…1-3 ft
Sabine Lake…1-3 ft
Port O’Connor, TX to High Island, TX including Galveston Bay…1-3 ft
The deepest water will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large and dangerous waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances. For information specific to your area, please see products issued by your local National Weather Service forecast office.
WIND: Hurricane conditions are expected within the hurricane warning area during the next few hours, with tropical storm conditions already occuring. Tropical storm conditions will continue to spread onshore within portions of the tropical storm warning areas during the next several hours.
RAINFALL: Today through Saturday, Delta is expected to produce 5 to 10 inches of rain, with isolated maximum totals of 15 inches, from southwest into central Louisiana. These rainfall amounts will lead to significant flash, urban, small stream flooding, along with minor to major river flooding.
For extreme east Texas into northern Louisiana, southern Arkansas, and western Mississippi, Delta is expected to produce 3 to 6 inches of rain, with isolated maximum totals of 10 inches. These rainfall amounts will lead to flash, urban, small stream, and isolated minor river flooding.
As the remnants of Delta move farther inland, 1 to 3 inches of rain, with locally higher amounts, are expected in the Tennessee Valley and Mid Atlantic this weekend. There is a potential for 3 to 6 inches in the Southern Appalachians, which could lead to isolated flash, urban, and small stream flooding.
TORNADOES: A few tornadoes are possible this afternoon through tonight over southern portions of Louisiana and Mississippi.
SURF: Swells from Delta are affecting portions of the northern and western Gulf coast. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.
TECHNICAL DISCUSSION
Reports from an Air Force Reserve Hurricane Hunter aircraft and WSR-88D Doppler radar data indicate that Delta has weakened some more since the last advisory. The eye structure on the radar has become less organized, with about 50 percent of the eyewall remaining in the northern semicircle. The aircraft reported maximum 700-mb flight-level winds have decreased to the 100-105 kt range, along with maximum SFMR surface wind estimates in the 80-85 kt range. In addition, the central pressure has risen to near 966 mb. Based on these data, the initial intensity is lowered to 90 kt.
The initial motion is now north-northeastward or 015/12 kt, with the hurricane moving between a deep-layer ridge over the eastern Gulf of Mexico and a mid- to upper-level trough over the U.S. Southern
Plains. This motion should continue through the next 24 h or so, followed by a turn toward the northeast as Delta or its remnants move along the southern edge of the mid-latitude westerlies. While the track guidance remains tightly clustered, the guidance is a little faster than the previous run. So, the new track forecast is similar in direction, but slightly faster than the previous one. The forecast track has the center of Delta making landfall in southwestern Louisiana in the next few hours and then moving across central and northeastern Louisiana tonight and Saturday morning. After that, the system should move across northern Mississippi into the Tennessee Valley before it dissipates.
Increasing vertical shear and decreasing oceanic heat content along the forecast track could cause a little more weakening in the last few hours before landfall. However, there will still be significant impacts from winds and storm surge (see Key Messages below). After landfall, rapid weakening is anticipated, with Delta expected to weaken to a tropical storm tonight and to a tropical depression by Saturday afternoon. As in the last advisory, the cyclone is forecast to dissipate between 60-72 h based on the consensus of the global models.
