AccuWeather forecasters are warning that the western Caribbean could face extreme impacts from Tropical Storm Melissa as the storm will barely move for nearly a week.
* Tropical Storm Melissa is expected to become a hurricane Oct. 24.
* There is significant uncertainty in the track and intensity forecast of Melissa.
* The National Hurricane Center is now predicting Melissa could be a Category 3 storm Oct. 27 with 120-mph winds.
* See latest spaghetti models and what Florida can expect.
While portions of the Caribbean brace for impacts from Tropical Storm Melissa, Florida residents should keep a wary eye on the storm.
"There is significant uncertainty in the track and intensity forecast of Melissa," the National Hurricane Center said, but added it is now predicting Melissa will become a major hurricane by early next week.
Melissa is forecast to make landfall on Hispaniola, but determining where it goes after that is proving to be "very challenging."
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A major hurricane is one that's at least a Category 3 storm, with maximum sustained winds of 111 mph.
Melissa is predicted to become a hurricane on Friday, Oct. 24, the Hurricane Center said, changing an earlier forecast of Melissa becoming a hurricane Thursday, Oct. 23.
Could Melissa impact Florida?
"The longer Melissa tracks to the west, the greater the chance of an impact on the U.S.," said AccuWeather Chief Meteorologist Bernie Rayno said.
"The chances of a direct U.S. hit from Melissa are low right now, but it is still an option," said AccuWeather Lead Hurricane Expert Alex DaSilva. "The U.S. concern for impacts will be in the Florida Peninsula, especially the lower portion of the Peninsula and the Keys."
Even the East Coast of the U.S. could feel some impacts from Melissa -- rain, wind and rough seas -- later this month, even if the center remains at sea, according to AccuWeather.
Here's what you should know.
Highlights on what Tropical Storm Melissa is doing now
Special note on the NHC cone: The forecast track shows the most likely path of the center of the storm. It does not illustrate the full width of the storm or its impacts, and the center of the storm is likely to travel outside the cone up to 33% of the time.
* Location: 320 miles south-southwest of Port Au Prince, Haiti; 300 miles southeast of Kingston, Jamaica; 961 miles southeast of Naples
* Maximum sustained winds: 50 mph
* Movement: west at 2 mph
* Pressure: 1000 mb
Tropical Storm Melissa: What you need to know
At 5 p.m., the center of Tropical Storm Melissa was located near latitude 14.4 North, longitude 74.3 West.
Melissa is moving slowly toward the west-northwest near 2 mph. A slow forward speed and a gradual turn to the northwest or north-northwest is forecast during the next couple of days, followed by a turn back westward by this weekend.
On the forecast track, Melissa is expected to approach Jamaica and the southwestern portion of Haiti later this week.
Maximum sustained winds are near 50 mph with higher gusts. Some slow strengthening is forecast during the next few days, and Melissa could become a hurricane by Friday, with more substantial intensification forecast by this weekend.
Tropical-storm-force winds extend outward up to 115 miles from the center.
The estimated minimum central pressure is 1000 mb.
Spaghetti models for Tropical Storm Melissa
Special note about spaghetti models: Illustrations include an array of forecast tools and models, and not all are created equal. The hurricane center uses only the top four or five highest performing models to help make its forecasts.
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See map of hurricane/tropical storm watches, warnings issued for Florida
As of 5 p.m. Oct. 22, no watches or warnings associated with Tropical Storm Melissa have been issued for Florida or the U.S.
What tropical storm, hurricane warnings have been issued for Tropical Storm Melissa?
* A hurricane watch is in effect for:
* A tropical storm watch is in effect for:
A hurricane watch means 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 tropical storm watch means tropical storm conditions are possible within the watch area, generally within 48 hours.
How strong is Tropical Storm Melissa and where is it going?
Tropical Storm Melissa is drifting along in the central Caribbean, moving west-northwest at 2 mph.
A slow forward speed and a gradual turn to the northwest or north-northwest is forecast during the next couple of days, followed by a turn back westward by this weekend.
Is there a hurricane coming toward Florida?
"There is significant uncertainty in the track and intensity forecast of Melissa," the National Hurricane Center said, adding "this is a very challenging track forecast" and "the intensity forecast has its own share of challenges."
"Most of the guidance shows significant or even rapid intensification in days 3-5. The day 5 forecast (Monday, Oct. 27) now shows Melissa becoming a major hurricane," with 120-mph winds, the National Hurricane Center said.
"The longer Melissa tracks to the west, the greater the chance of an impact on the U.S.," Rayno said.
"The U.S. concern for impacts will be in the Florida Peninsula, especially the lower portion of the Peninsula and the Keys. Strong westerly winds, driven by the jet stream, should prevent the storm from tracking into Texas, Louisiana and the panhandles of Mississippi, Alabama and Florida next week."
"At this time, I think the chances of any direct or even indirect impacts on Florida, beyond waves and rip currents, are very low, around 15% or so," said DaSilva via email Oct. 21.
"If Florida were to see any impacts, it would likely be around the middle of next week -- Wednesday through Friday (Oct. 29-31). There's nothing imminent right now, but it's something to keep an eye on over the next few days as we monitor trends and model data."
Key messages from the National Hurricane Center: What you need to know about Tropical Storm Melissa
Current forecast: Where is Tropical Storm Melissa going and how strong could it get?
* As of 5 p.m.: 50 mph
* 12 hours: 50 mph
* 24 hours: 60 mph
* 36 hours: 60 mph
* 48 hours: 65 mph
* 60 hours: 70 mph
* 72 hours: 80 mph
* 96 hours: 115 mph
* 120 hours: 130 mph
"The day 5 forecast (Monday, Oct. 27) now shows Melissa becoming a major hurricane, and further upward adjustments may be necessary in subsequent cycles," the National Hurricane Center said. "The intensity forecast is also more uncertain than usual, in large part related to the track uncertainty ... and further upward adjustments may be necessary."
What impact could Tropical Storm Melissa have and what areas could be affected?
* Wind: Hurricane conditions are possible within the watch area in Haiti beginning on Friday. Tropical storm conditions could begin in Jamaica late on Thursday or Friday.
* Rainfall: Melissa is expected to bring 5 to 10 inches of rain to the southern Dominican Republic, southern Haiti, and eastern Jamaica through Saturday, with locally higher amounts possible. Additional heavy rainfall is possible beyond Saturday. However, uncertainty in Melissa's track and forward speed reduces confidence in exact totals. Significant, life-threatening flash flooding and numerous landslides are possible.
* Surf: Swells generated by Melissa are expected to spread to Hispaniola, Jamaica, and eastern Cuba during the next couple of days.
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This story has been updated to include new information.