1. Extremely dangerous storm surge and hurricane conditions areexpected within portions of the northern Yucatan Peninsula ofMexico beginning tonight, and a Hurricane Warning is in effect.

2. Heavy rainfall will affect portions of the Cayman Islands, western Cuba and the northern Yucatan Peninsula through midweek. This rainfall could lead to significant flash flooding and mudslides. The potential for heavy rain and flash flooding will increase across portions of the central Gulf Coast, Tennessee Valley, and southeastern United States as Delta moves inland later this week.

3. Delta is forecast to approach the northern Gulf Coast late thisweek as a hurricane. While there is large uncertainty in the trackand intensity forecasts, there is a significant risk of dangerousstorm surge, wind, and rainfall hazards along the coast fromLouisiana to the western Florida Panhandle beginning Thursday nightor Friday. Residents in these areas should ensure they have theirhurricane plan in place and monitor updates to the forecast ofDelta.

CHANGES WITH THIS ADVISORY:

The government of Mexico has extended the Hurricane Warning westward along the north coast of the Yucatan Peninsula to Dzilam.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Hurricane Warning is in effect for...
- Tulum to Dzilam Mexico
- Cozumel

A Tropical Storm Warning is in effect for...
- Cayman Islands including Little Cayman and Cayman Brac
- Cuba province of Pinar del Rio
- Isle of Youth
- Punta Herrero to Tulum
- Dzilam to Progresso

A Tropical Storm Watch is in effect for...
- Cuba province of La Habana

A Hurricane Warning means that hurricane conditions are expected somewhere within the warning area. 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 within 36 hours.

A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours.

For storm information specific to your area, please monitor products issued by your national meteorological service.

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.

STORM SURGE: An extremely dangerous storm surge will raise water levels by as much as 6 to 9 feet above normal tide levels along coast of the Yucatan peninsula within the hurricane warning area, near and to right of where the center makes landfall. Near the coast, the surge will be accompanied by large and dangerous waves.

WIND: Tropical storm conditions are expected in the Cayman Islands later this morning. In the Yucatan Peninsula, hurricane conditions are expected in the warning area early Wednesday, with tropical storm conditions expected later today. Tropical storm conditions are expected in the tropical storm warning area tonight and Wednesday. In Cuba, tropical storm conditions are expected tonight in the warning area and possible in the watch area near the same time.

RAINFALL: Delta is expected to produce 4 to 6 inches of rain, with isolated maximum totals of 10 inches, across portions of the northern Yucatan Peninsula through midweek. This rainfall may result in areas of significant flash flooding.

Over the next few days, Delta is expected to produce 2 to 4 inches of rain, with isolated higher amounts, across portions of the Cayman Islands and western Cuba. This rainfall may result in areas of flash flooding and mudslides.

Later this week, Delta is expected to bring heavy rainfall to portions of the central Gulf Coast, Tennessee Valley, and southeastern United States.

SURF: Swells generated by Delta will be affected land areas around the northwestern Caribbean Sea for the next day or so. These swells are likely to cause lifethreatening surf and rip current conditions. Please consult products from your local weather office.

At 500 AM EDT (0900 UTC), the center of Hurricane Delta was located near latitude 17.5 North, longitude 81.3 West. Delta is moving toward the westnorthwest near 15 mph (24 km/h). A faster northwestward motion is expected to begin later today through Wednesday night. On the forecast track, the center of Delta is expected to pass southwest of the Cayman Islands this morning, and move over the northeastern portion of the Yucatan peninsula early Wednesday. Delta is forecast to move over the southern Gulf of Mexico Wednesday afternoon, and be over the southern or central Gulf of Mexico through Thursday. Data from an Air Force Reserve Hurricane Hunter aircraft indicate that maximum sustained winds have increased to near 100 mph (155 km/h) with higher gusts. Some strengthening is forecast during the next 48 hours, and Delta is expected to be a major hurricane over the Yucatan Peninsula Wednesday and over the Gulf of Mexico through Thursday.

Hurricaneforce winds extend outward up to 25 miles (35 km) from the center and tropicalstormforce winds extend outward up to 90 miles (150 km).

The latest minimum central pressure reported by an Air Force Reserve Hurricane Hunter aircraft is 968 mb (28.59 inches).

Delta has maintained a very deep central dense overcast during thepast several hours, with overshooting cloud-top temperatures to-90C, and perhaps hints of an eye trying to emerge. On the last pass through the center, the Air Force plane reported a 4-mb pressure fall in one hour to 968 mb, with believable SFMR values of 80-85 kt. Thus, the initial wind speed is set to 85 kt.

The hurricane is in the midst of a very impressive rapidintensification episode, having strengthened over 50 kt during the past 24 hours. I honestly don't see much that will stop it until itreaches Yucatan, due to low vertical wind shear, high deep-layermoisture, and the very warm and deep waters of the northwesternCaribbean. This is also supported by SHIPS rapid intensification probabilities that are well above 50 percent for most categories. Thus, the intensity forecast is raised to 115 kt near Yucatan landfall, closest to the HWRF forecast model, which has been a good performer this year, especially after ingesting NOAA radar data. Some weakening is expected due to land interaction, but conditions look ripe for re-intensification over the Gulf of Mexico. Almost all the guidance is higher, now showing Delta reaching category 4 status in the 2-to-3 day time frame, and the new NHC intensity forecast reflects this likelihood. However, an increase in southwesterly shear and cooler shelf waters near the northern Gulf coast should promote weakening, and little change has been made to the intensity forecast near landfall. Delta is moving much faster this morning to the west-northwest, with the latest estimates at about 13 kt. A strengthening mid-level ridge across Florida should steer the hurricane to the west-northwest or northwest during the next couple of days. Likely because of the deterioration of Gamma, model guidance is showing less poleward motion before Yucatan, and the official track is shifted to the west for the first day or so. Over the Gulf of Mexico, Delta should slow down and turn northward ahead of a trough moving eastward across Texas in a few days. Model guidance has again shifted westward, like the last cycle, and the official forecast is trended in that direction. However, it remains slightly east of the model consensus, due to a notable westward bias in some of the guidance during this hurricane season.Users are reminded to not focus on the details of the track orintensity forecasts, as the average 4-day track error is around 150miles and the average 4-day intensity error is close to 15 mph.