00:57 Rainfall Forecast Increased Ahead of Tropical Storm Beta's Crawl Along Texas Tropical Storm Beta has stalled in the western Gulf of Mexico, which will eventually set the storm up for a slow scrape of the Texas coast into next week. Beta poses a major threat of rainfall and coastal flooding to the Texas and Louisiana coasts.

At a Glance Hurricane Irma is likely to impact parts of the Southeast U.S. as an intense hurricane.

Its U.S. impact is likely to begin this weekend in Florida.

However, there is still uncertainty which areas may be hardest hit.

Irma will then likely track into the Southeast U.S. early next week.

Details on Irma's impact for the rest of the Southeast U.S. remain uncertain.



Hurricane Irma, already the most intense Atlantic hurricane in 12 years, is an increasingly dangerous threat to Florida and parts of the Southeast beginning this weekend.

(COMPREHENSIVE HURRICANE IRMA COVERAGE: Hurricane Central )

However, we're still far enough out that key uncertainties remain.

Here is what we know, and don't yet know, right now.

South Florida Threat

It's important to mention first the average error in the National Hurricane Center (NHC) forecast of the center of a tropical cyclone 4 to 5 days out ranges from 175 to 225 miles.

(MORE: Cone of Uncertainty's Facts and Myths )

That means pinpointing precise impacts in specific locations is not yet possible for the Sunshine State. However, Irma will likely remain a formidably intense hurricane as it approaches South Florida this weekend.

If Irma's center tracks toward the southern edge of the cone, impacts on South Florida would be much less severe.

If, however, Irma's center tracks toward the center or northern half of the cone this weekend, an intense eyewall strike on South Florida would occur, with potentially devastating, destructive winds, in addition to life-threatening storm surge flooding and torrential rainfall.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/staticmaps/DCT_SPECIAL20_1280x720.jpg" srcset="https://s.w-x.co/staticmaps/DCT_SPECIAL20_1280x720.jpg 400w, https://s.w-x.co/staticmaps/DCT_SPECIAL20_1280x720.jpg 800w" > Hurricane Irma Forecast Path (The red-shaded area denotes the potential path of the center of the tropical cyclone. The NHC does not issue the forecast path beyond five days out. Note that impacts (particularly heavy rain, high surf, coastal flooding) with any tropical cyclone may spr) (The red-shaded area denotes the potential path of the center of the tropical cyclone. The NHC does not issue the forecast path beyond five days out. Note that impacts (particularly heavy rain, high surf, coastal flooding) with any tropical cyclone may spr)

Regardless, conditions in South Florida may go downhill as soon as midday Saturday, making any last-hour preparations difficult.

(MORE: Are You in an Evacuation Zone? )

For now, get your hurricane plan ready to implement and follow instructions from local government and emergency managers. This is not a hurricane you want to risk riding out. If a mandatory evacuation is issued, you are strongly urged to leave.

Rest of Southeast U.S. Threat

Beyond South Florida, the rest of the forecast remains uncertain, a common issue with hurricane forecasts beyond five days out and still over 1,000 miles from the mainland U.S.

This is illustrated clearly by ensemble model forecast tracks from the European Centre for Medium-Range Weather Forecasts (ECMWF), compiled Sept. 4 at 8 p.m. EDT. The closer the tracks are, the more confident the forecast.

In this case, the spread of tracks remains from toward the Carolinas to the northern Gulf Coast, not to mention a few solutions tracking Irma over or south of Cuba.

(MORE: What to Know About "Spaghetti Models" )

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/irma-tracks-ecmwf-5sep0z.jpg" srcset="https://s.w-x.co/irma-tracks-ecmwf-5sep0z.jpg 400w, https://s.w-x.co/irma-tracks-ecmwf-5sep0z.jpg 800w" > ECMWF ensemble forecast tracks for Hurricane Irma from the Sept. 5, 2017, 00 UTC model run.

The linchpin to the forecast is exactly when and where Irma makes its northward turn.

There appear to be three general scenarios.

Scenario A: Sooner Turn Would Resemble a Matthew Path

If Irma's center turns earliest relative to the other scenarios, that would raise the threat of an eventual eyewall strike in the Carolinas, with the chance of an eyewall strike along at least parts of Florida's East Coast, as well.

This would be similar to Hurricane Matthew's path in October 2016.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/matthew-history.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/matthew-history.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/matthew-history.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > Hurricane Matthew's track history in late September - early October 2016.

Scenario B: Track Over/Near Much of Florida Peninsula

A slightly later turn northward could take Irma's center over much of the Florida Peninsula.

That would weaken Irma over land, but not enough to avoid widespread wind damage (downed trees, powerlines, some structural damage) even in inland locations of the Florida Peninsula, in addition to storm surge flooding that would occur at the coast.

(MORE: Beware of 'I' Hurricanes )

Scenario C: Late Turn Means Northern Gulf Coast Landfall

This scenario, assuming Irma turns later than the other scenarios, could spare much of the Florida Peninsula (especially southeast Florida) the worst from Irma.

Instead, this track could bring Irma over the eastern Gulf of Mexico, with a landfall somewhere along the north-central or northeast Gulf coast early next week.

This could allow for some restrengthening of Irma, assuming any earlier land interaction in Cuba or Hispañola doesn't take a toll, leading to a formidable hurricane strike on the northern Gulf Coast.

At this time, all three scenarios are still on the table.

Irma's Size = Threats Regardless

Irma will be a large hurricane, so, despite the uncertainty in its track, you can expect the following along much of the Southeast and at least eastern Gulf Coasts:

Increasing high surf along the Southeast coast by Thursday, with some coastal flooding possible near high tide from the Outer Banks south possible as soon as Friday.

Dangerous, life-threatening storm surge flooding to the north and east of Irma's path.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/staticmaps/DCT_SPECIAL26_1280x720.jpg" srcset="https://s.w-x.co/staticmaps/DCT_SPECIAL26_1280x720.jpg 400w, https://s.w-x.co/staticmaps/DCT_SPECIAL26_1280x720.jpg 800w" > Irma's Current Wind Field Size (Analysis of Irma's current wind field size, according to the latest NHC advisory. Areas with hurricane-force winds shown in purple.) (Analysis of Irma's current wind field size, according to the latest NHC advisory. Areas with hurricane-force winds shown in purple.)

Furthermore, a threat of rainfall flooding and strong winds capable of triggering power outages, downing trees and perhaps some structural damage will likely occur to some degree well inland from wherever Irma makes landfall into a swath of the Southeast early next week.

Again, exactly where the heaviest rain and strongest winds will occur depends on the uncertain future path of Irma.

Residents from the northeast Gulf Coast to the Carolinas, including all of Florida, should check back with weather.com or any trusted source for weather information to get the latest on Irma, and heed any evacuation notices from

As the days go by, uncertainty will narrow and we'll be able to pinpoint specific impacts of Irma on the mainland.

(MORE: Retired Atlantic Tropical Storm and Hurricane Names )

In the meantime, now is an excellent time to develop or refresh your hurricane plan. The Federal Alliance for Safe Homes has an excellent site to help.

Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Facebook and Twitter .