Marco likely to go east of Houston, still lots of questions about Laura

Good afternoon. We’re finally starting to get a better handle on what is likely to happen with Tropical Storm Marco today, which is a good thing because the storm may make landfall as soon as Monday along the northern Gulf Coast. We have less certainty about Tropical Storm Laura, which is a cyclone most of the Gulf Coast needs to continue to watch.

Tropical Storm Marco

Marco has done two things today that increase our confidence that it will follow a more northerly track across the Gulf of Mexico. For one, it has continued to intensify, up to 65 mph sustained winds as of 1pm CT, allowing it more control over its track. Second, an Air Force reconnaissance plane found a center east of where it was expected. All of this suggests the storm will track more toward Louisiana rather than Texas over the next two days—if you read our early morning post on Space City Weather, this was Scenario One that we outlined.

While we cannot rule out a more westward track toward Texas (and of course, we’ll continue to monitor the system), at this point it appears most likely that Marco will come ashore over Louisiana, or even Mississippi. Because we can expect the strongest winds, waves, and rains to the east of the land-falling center, this means the most likely outcome for Houston is moderate to minimal effects. The northern Gulf of Mexico coast will need to watch Marco closely over the next couple of days. Although Marco now seems likely to become at least a moderate hurricane, it should encounter enough wind shear to weaken to a tropical storm before landfall a couple of days from now.

Tropical Storm Laura

This system has strengthened some today as its center has become a little better defined. Shortly before 1pm CT, the center was located just offshore the southern coast of Puerto Rico, and it may briefly come ashore later today. In this morning’s post we outlined some of the factors surrounding Laura’s potential to intensify over the next day or two as it encounters Puerto Rico, Hispaniola, and Cuba (i.e. to shred, or not to shred). From this image you can see how predicting this is touch-and-go.

Because we don’t know precisely how much time the storm will spend over this at-times mountainous terrain, there’s not a whole lot intelligible we can say about Laura’s intensity upon entering the Gulf of Mexico on Monday. However, assuming some semblance of a circulation remains by then, conditions in the central Gulf of Mexico would allow Laura to strengthen, quite possibly into a hurricane.

We still have lots of questions about Laura’s track after reaching the Gulf. The storm seems eventually destined for Louisiana or Texas, but it could come as far east as the Florida Panhandle. If anything, the models this afternoon are leaning ever-so-slightly toward Louisiana over Texas, but we’ve seen plenty of flip-flops so our confidence is quite low. If Laura were to come to Texas, we probably would begin to see its effects by Wednesday night or Thursday.

ON THE BRIGHTER SIDE: I think we’ll have a better handle on Laura’s track over the next 24 to 36 hours, which should still allow several days for final storm preparations—if needed. So as usual, we’re asking you to hang in there with us for a little while longer. And if we can get through Laura, it looks like the tropics may quiet down for a bit, allowing all of us to take a breath.

Matt will have our next update, no later than 9pm CT Saturday.