Weather forecast models perform incredibly complex tasks. When you consider that within less than three days, the margin of error in a forecast track is less than 150 miles, that is impressive given all the factors involved in such calculations. But models don’t always agree and when one of the most respected of those happens to be an outlier in a forecast, people pay attention.
Such is the case with current Tropical Storm Laura. As of writing this, Laura was traversing the far western end of Cuba headed for the Gulf of Mexico, where it will undoubtedly become a hurricane relatively early in the day on Tuesday. From there, it will traverse the Gulf just to the south of a ridge of high pressure that is pushing to the west at the same time.
For the uninitiated, hurricanes typically cannot move into areas of high pressure, especially if they are fairly strong like this one. As a result, they travel around the periphery looking for a weak spot to make a turn to the north where they are naturally drawn.
As Laura moves across the Gulf, there don’t appear to be any significant impediments to its development and intensification. Intensity modeling ranges from a category 1 to a category 4 hurricane at landfall. The National Hurricane Center, which is predicting steady intensification for Laura, believes it could be near or at major hurricane strength when it makes landfall in the wee hours of Thursday morning.
Now, back to that forecast track. At the moment, Houston is on the far western edge of the NHC’s “cone of uncertainty,” which covers all of extreme eastern Texas and western Louisiana. That cone will shrink as the storm gets closer, but there is still quite a bit of uncertainty thanks to the European forecast model.
The Euro is one of the most respected forecasts when it comes to both climate and hurricanes. As of now, it still shows a pretty wide spread ranging from the coastal bend area of the Texas coast all the way to the Texas-Louisiana border. The other reliable forecast models have all bunched fairly tightly together around a spot just east of Texas in extreme western Louisiana, but not the Euro.
Now, that could change overnight and into tomorrow. The closer we get, the better the guidance becomes and the narrower that cone. If the other models remain consistent and the Euro makes a shift east — it already shifted a bit that way on its Monday evening run — we can start to have more confidence that Houston will escape a direct hit.
But, if it remains west and south and some of the other models begin to adjust with it, we could be in the direct path of a large and dangerous storm.
By the time you read this, we may actually have more clarity and we will continue to update things as we get more information. But, for now, be aware that while we are close to being in the clear, we aren’t there yet.