1. Hurricane conditions and a dangerous storm surge are expected in portions of the Hurricane Warning area in the eastern Yucatan Peninsula of Mexico beginning late tonight or early Thursday. 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 will likely be issued for part of this area tonight.

3. Through the weekend, heavy rainfall across the Cayman Islands as well as 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 Tropical Storm Warning is in effect for...
- Cayman Islands
- 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 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 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: Strong gusty winds are likely over portions of the Cayman Islands for the next few hours. Tropical storm conditions are possible along the southern coast of Cuba within the watch area for the next several hours. Hurricane conditions are expected within the warning area in the Yucatan Peninsula of Mexico late tonight or early Thursday, with tropical storm conditions beginning as early as this evening.

RAINFALL: The system is expected to produce the following rainfall amounts: Over the Cayman Islands and central to northern 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 the central to northern Veracruz state of Mexico, 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 late tonight or early Thursday. 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 Thursday. These swells are likely to cause life threatening surf and rip current conditions. Please consult products from your local weather office.

At 500 PM EDT (2100 UTC), the center of Hurricane Grace was located near latitude 19.7 North, longitude 83.7 West. Grace is moving toward the west northwest near 16 mph (26 km/h). A general west northwestward to westward motion is expected for the next several days. On the forecast track, Grace is expected to make landfall in the eastern Yucatan Peninsula Thursday morning, move over the Yucatan Peninsula on Thursday, and move over the southwest Gulf of Mexico Thursday night or early Friday. Maximum sustained winds are near 80 mph (130 km/h) with higher gusts. Some strengthening is possible before the center of Grace reaches the Yucatan Peninsula. Weakening will occur while the center moves over the Yucatan Peninsula on Thursday, with restrengthening expected when Grace moves over the southwest Gulf of Mexico on Friday. Hurricane force winds extend outward up to 15 miles (30 km) from the center and tropical storm force winds extend outward up to 140 miles (220 km). Tropical storm force wind gusts were reported over portions of western Cuba this afternoon. The estimated minimum central pressure is 992 mb (29.30 inches).

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A ragged eye appeared for a while on visible satellite imagery, but it has recently been obscured by cumulonimbus tops. The overall cloud pattern has been maintaining its organization with some convective banding features and very cold cloud tops, mainly over the eastern portion of the circulation. The current intensity estimate is set at 70 kt, which is a blend of Dvorak estimates from TAFB and SAB. Another Air Force Reserve Hurricane Hunter aircraft is scheduled to investigate the hurricane in a few hours to provide another intensity estimate.

Grace will continue to move over waters of very high oceanic heat content prior to reaching the east coast of the Yucatan Peninsula, which of course favors intensification. Aside from moderate northwesterly shear, a possible impediment to strengthening is a northeast to southwest-oriented shear axis located just to the northwest of the hurricane. Nonetheless, some intensification is anticipated before landfall in Yucatan, with restrengthening over the Bay of Campeche. The official intensity forecast continues to be in general agreement with the multi-model consensus predictions, IVCN and HCCA.

Grace is moving west-northwestward, or about 285/14 kt. There has been essentially no change to the track forecast philosophy. Grace should maintain a west-northwestward to westward motion, on the southern periphery of a strong subtropical ridge, for the next several days. The official track forecast is very similar to the previous one and about on top of the latest multi-model consensus, TVCA.

A Hurricane Watch will likely be required for a portion of the coast of eastern mainland Mexico tonight.