1. Hurricane conditions and a dangerous storm surge are expected in portions of the Hurricane Warning area in the eastern Yucatan Peninsula of Mexico during the next several hours. Preparations to protect life and property should be rushed to completion.

2. There is an increasing risk of hurricane conditions and dangerous storm surge in portions of eastern mainland Mexico beginning late Friday, and a Hurricane Watch is in effect for part of this area.

3. Through the weekend, heavy rainfall across central and northern portions of the Yucatan Peninsula and Veracruz State should lead to flash and urban flooding. In addition, the heavy rainfall from Grace will be capable of producing mudslides in Veracruz.

CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Hurricane Warning is in effect for...
- Yucatan Peninsula of Mexico from Cancun to Punta Herrero, including Cozumel A Hurricane Watch is in effect for...
- The coast of mainland Mexico from Puerto Veracruz to Cabo Rojo A Tropical Storm Warning is in effect for...
- Yucatan Peninsula of Mexico from north of Cancun to Campeche
- Yucatan Peninsula of Mexico from south of Punta Herrero to Puerto Costa Maya A Tropical Storm Watch is in effect for...
- Southern coast Cuban province of Pinar del Rio, as well as Isla de la Juventud
- The coast of mainland Mexico north of Cabo Rojo to Puerto de Altamira 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 Hurricane Watch means that hurricane conditions are possible within the watch area. A watch is typically issued 48 hours before the anticipated first occurrence of tropical storm force winds, conditions that make outside preparations difficult or dangerous. A hurricane warning will likely be required for portions of the Watch area later this morning or afternoon. 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. Interests elsewhere in eastern mainland Mexico should monitor the progress of Grace. For storm information specific to your area, please monitor products issued by your national meteorological service.

Key messages for Grace can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDAT2, WMO header WTNT42 KNHC and on the web at www.hurricanes.gov/graphics_at2.shtml?key_messages.

WIND: Hurricane conditions are expected within the warning area in the Yucatan Peninsula of Mexico during the next few hours, and tropical storm conditions are continuing to spread onshore. Hurricane and tropical storm conditions will spread inland across the Yucatan Peninsula during the day today. Hurricane conditions are possible in the hurricane watch area in mainland Mexico by late Friday, and tropical storm conditions are possible in the tropical storm watch area in mainland Mexico by late Friday. Tropical storm conditions are possible along the southern coast of Cuba within the watch area for the next several hours.

RAINFALL: Grace is expected to produce the following rainfall amounts: Over north central portions of the Yucatan Peninsula... 4 to 8 inches of rain with isolated maximum totals of 12 inches are expected through Friday. Heavy rainfall from Grace will likely result in areas of flash and urban flooding. Over central to northern Veracruz, northern Puebla and into Hidalgo... 5 to 10 inches of rain with isolated maximum totals of 15 inches are expected from Friday through Sunday. Heavy rainfall from Grace will likely result in areas of flash and urban flooding, and will also be capable of producing mudslides.

STORM SURGE: A dangerous storm surge will raise water levels by as much as 3 to 5 ft above normal tide levels along the immediate coast near and to the north of where the center makes landfall in the northeastern Yucatan Peninsula later this morning, and along the eastern mainland coast of Mexico Friday night or early Saturday. Near the coast, the surge will be accompanied by large and destructive waves.

SURF: Swells generated by Grace will spread westward from Jamaica and the Cayman Islands to the southern coast of Cuba and the Yucatan Peninsula of Mexico through today. These swells are likely to cause life threatening surf and rip current conditions. Please consult products from your local weather office.

At 400 AM CDT (0900 UTC), the center of Hurricane Grace was located near latitude 20.0 North, longitude 87.2 West. Grace is moving toward the west near 17 mph (28 km/h). A general westward to west northwestward motion is expected through Friday, followed by a general westward to west southwestward motion. On the forecast track, Grace is expected to make landfall in the eastern Yucatan Peninsula during soon, move across the Yucatan Peninsula today, and move over the southwest Gulf of Mexico late tonight through Friday. Maximum sustained winds are near 80 mph (130 km/h) with higher gusts. Some slight strengthening is still possible before landfall on the Yucatan Peninsula. Grace is expected to weaken as it crosses Yucatan, but re intensification is expected when the center reaches the Gulf of Mexico. Hurricane force winds extend outward up to 35 miles (55 km) from the center and tropical storm force winds extend outward up to 140 miles (220 km). A Weatherflow station located at Cancun, Mexico, recently measured a sustained wind of 56 mph (88 km/h) and a gust to 79 mph (127 km/h), while another Weatherflow station located at Puerto Morelos, Mexico, recently measured a sustained wind of 51 mph (83 km/h) a gust to 70 mph (113 km/h). On Cozumel, a sustained wind of 41 mph (66 km/h) and a gust to 60 mph (96 km/h) was observed at the Cozumel Lighthouse, while a sustained wind of 40 mph (77 km/h) and a gust to 64 mph (103 km/h) were measured by a Weatherflow site near the airport. The estimated minimum central pressure is 986 mb (29.12 inches).

After a brief convective hiatus between 0400-0700 UTC, deep convection in the inner-core region has increased and become better organized during the past couple of hours. An Air Force Reserve Hurricane Hunter aircraft investigating Grace more than 4 hours ago reported a central pressure of 986 mb -- down 2 mb from previous passes -- and a maximum 700-mb flight-level wind speed of 74 kt on its last leg northbound around 0500 UTC. The 74-kt flight-level wind equates to about a 67-kt surface wind speed. These data supported maintaining a 70-kt intensity at 0600 UTC. The upper-level outflow remains symmetrical and has been expanding somewhat over the past few hours.

The initial motion is 280/15 kt based on the earlier recon fixes and passive microwave satellite data. Grace should continue to move generally westward for the next 48 hours, crossing the coast of the eastern Yucatan Peninsula within the next couple of hours, followed by a track across the Yucatan and emergence over the Bay of Campeche by 24 hours, with a subsequent landfall along the eastern coast of mainland Mexico shortly after the 48-hour forecast period. This track scenario is consistent with the latest 0000 UTC global and regional models, which show the strong deep-layer ridge to the north of Grace maintaining its expansive presence across the western Atlantic, Gulf of Mexico, and northern Mexico. After the second landfall, Grace is expected to turn west-southwestward and dissipate over the mountains of central Mexico by 72 hours. The new NHC forecast track is similar to the previous advisory track, and lies along the northern edge of the tightly packed consensus track models.

Given the recent improvement in Grace's inner-core convective structure noted in high-resolution infrared satellite imagery, some slight strengthening to 75 kt could still occur just prior to landfall this morning. Weakening will commence once Grace moves inland over Yucatan, with re-strengthening expected after the cyclone emerges over the Bay of Campeche where the vertical wind shear is forecast to decrease below 10 kt. Grace is expected to be a hurricane when the second landfall occurs along the coast of mainland Mexico, with the cyclone possibly reaching a peak intensity of 75 kt shortly after the 48-hour period. After final landfall in mainland Mexico, Grace should quickly weaken and dissipate over the mountains of Mexico by 72 hours, if not sooner. The remnants of Grace are expected to emerge over the eastern North Pacific and possibly re-develop there, but the uncertainty of whether this will be the original center or a new center precludes forecast points over the Pacific at this time.

A Hurricane Warning will likely be required for portions of the Hurricane Watch area of mainland Mexico later this morning or afternoon.