Discussion – 

0

Discussion – 

0

Delta regains Major Hurricane Strength; Tropical Storm & Surge Warnings expanded west along the Upper Texas Coast

Delta is on a strengthening trend this afternoon and has regained major hurricane status. Maximum sustained winds have increased to 115 miles per hour, with further strengthening likely this evening. The minimum central pressure is down to 959 millibars – down from 966 millibars three hours ago. The lower the pressure in a tropical cyclone, the more organized it is becoming.

More concerning to me is the significant expansion in the hurricane’s wind field. An expanding Windfield means more water being pushed toward the Texas, Louisiana, and Mississippi coastlines. Even though Texas will be on the western side of the hurricane, we anticipate some storm surge impacts on the Upper Texas Coast and in the Golden Triangle.

Advertisements

Hurricane warnings were expanded westward earlier to High Island (east side of the Bolivar Peninsula in Galveston County). Tropical storm warnings run southwest to Sargent on the Middle Texas Coast. Delta’s most severe impacts are likely to occur very near and east of the center’s landfall location. Unfourtinietly, the current track is very near Laura’s from six weeks ago.

Delta is forecast to weaken some as it approaches landfall on Friday. Do not be lulled into a false sense of security as Delta is expected to be a large and powerful hurricane when it reaches the coast.

CHANGES WITH THIS ADVISORY:

A Tropical Storm Warning is now in effect for the Texas coast west of San Luis Pass to Sargent.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for…

  • * High Island Texas to Ocean Springs Mississippi including Calcasieu Lake, Vermilion Bay, Lake Pontchartrain, Lake Maurepas, and Lake Borgne

A Hurricane Warning is in effect for…

  • * High Island Texas to Morgan City Louisiana
Advertisements

A Tropical Storm Warning is in effect for…

  • * West of High Island to Sargent Texas
  • * East of Morgan City Louisiana to the mouth of the Pearl River, including New Orleans
  • * Lake Pontchartrain and Lake Maurepas

A Tropical Storm Watch is in effect for… * East of the mouth of the Pearl River to Bay St. Louis Mississippi

A Storm Surge Warning means there is a danger of life-threatening inundation, from rising water moving inland from the coastline, during the next 36 hours in the indicated locations. For a depiction of areas at risk, please see the National Weather Service Storm Surge Watch/Warning Graphic, available at hurricanes.gov. This is a life-threatening situation. Persons located within these areas should take all necessary actions to protect life and property from rising water and the potential for other dangerous conditions. Promptly follow evacuation and other instructions from local officials.

A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. A warning is typically issued 36 hours before the anticipated first occurrence of tropical-storm- force winds, conditions that make outside preparations difficult or dangerous. Preparations to protect life and property should be rushed to completion.

A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area.

A Tropical Storm Watch means that tropical storm conditions are possible within the watch area.

For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service forecast office.

Discussion and Outlook

Advertisements

At 400 PM CDT (2100 UTC), the center of Hurricane Delta was located near latitude 24.8 North, longitude 93.4 West. Delta is moving toward the northwest near 12 mph (19 km/h), and this motion with a reduction in forward speed is expected this evening. A turn toward the north is forecast to occur late tonight, followed by a north-northeastward motion Friday and Friday night. On the forecast track, the center of Delta will move over the western Gulf of Mexico this evening, over the northwestern Gulf of Mexico on Friday, and then move inland within the hurricane warning area Friday afternoon or Friday night.

Reports from an Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds have increased to near 115 mph (185 km/h) with higher gusts. Delta is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Additional strengthening is possible tonight. Some weakening is possible as Delta approaches the northern Gulf coast on Friday, with rapid weakening expected after the center moves inland.

Hurricane-force winds extend outward up to 35 miles (55 km) from the center and tropical-storm-force winds extend outward up to 160 miles (260 km).

The minimum central pressure just reported by the Hurricane Hunter aircraft is 959 mb (28.32 inches).

Key messages for Delta can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT1, WMO header WTNT41 KNHC, and on the web at www.hurricanes.gov/text/MIATCDAT1.shtml.

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
  • Sabine Pass to Holly Beach, LA…4-7 ft
  • Morgan City, LA to Port Fourchon, LA…4-7 ft
  • Port Fourchon, LA to the Mouth of the Mississippi River…3-5 ft
  • Calcasieu Lake…3-5 ft
  • High Island, TX to Sabine Pass…2-4 ft
  • Mouth of the Mississippi River to Ocean Springs, MS…2-4 ft
  • Lake Borgne, Lake Pontchartrain, and Lake Maurepas…2-4 ft
  • Ocean Springs, MS 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

It is important to note that small changes in the track, structure, or intensity of Delta could have large impacts on where the highest storm surge occurs. Users are urged to stay tuned for possible changes and updates.

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 by Friday afternoon or evening, with tropical storm conditions expected within this area by early Friday. Tropical storm conditions are expected within the tropical storm warning areas on Friday, and are possible in the tropical storm watch area Friday night.

RAINFALL: Friday through Saturday, Delta is expected to produce 5 to 10 inches of rain, with isolated maximum totals of 15 inches, from southwest into south-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 Delta moves farther inland, 1 to 3 inches of rain, with locally higher amounts, are expected in the Tennessee Valley and Mid Atlantic this weekend.

TORNADOES: There is a risk of a few tornadoes beginning late tonight and continuing through Friday over southern portions of Louisiana and Mississippi.

SURF: Swells from Delta will begin to affect portions of the northern and western Gulf coast during the next several hours. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office.

Tags:

David Reimer

0 Comments

You May Also Like

Share to...