The remnants of Tropical Storm Harvey crossed the Yucatan Peninsula today and have recently emerged into the eastern Bay of Campeche. Ex-Harvey is expected to regenerate into a Tropical Depression or Storm tomorrow or Thursday, and is likely to make landfall in south-central Texas by late Friday. After that time, it is possible that Harvey could meander for several days, possibly causing serious flooding.

As of 00:00 UTC Wednesday, the remnants of Harvey were centered near 20.8°N 90.9°W, and were moving northwestward at about 10 mph. Maximum sustained winds were 25 knots (30 mph), with an estimated minimum pressure of 1009 mb. The National Hurricane Center (NHC) is extremely confident that Harvey will redevelop, giving a 90 percent chance of redevelopment within 48 hours and a near 100 percent chance within five days. This makes sense, given the favorable conditions and that practically all global models regenerate Harvey into at least a tropical depression by Thursday.

Surface observations indicate that a broad area of low pressure has developed with the remnants of Harvey, and the circulation is gradually becoming better defined. Deep convection has also begun to increase around the system, now that the center has emerged over water. Harvey is expected to remain in a favorable environment with light wind shear of less than 10 knots, mid-level relative humidity values above 60 percent, and very warm sea surface temperatures of near 30°C (86°F). It is unclear exactly when Harvey will develop a well-defined center. The sooner it develops a well-defined circulation, the stronger it is likely to become at landfall. Although conditions appear very favorable for Harvey to strengthen, its large size may limit rapid organization. However, if Harvey is able to quickly develop an inner core, more rapid intensification than predicted could take place due to the expected favorable conditions. The GFS and ECMWF models, as well as most of the intensity guidance, predict that Harvey will be a strong tropical storm at landfall. However, it is possible Harvey becomes a hurricane before landfall. The exact details on the future intensity of Harvey are uncertain as a well-defined circulation has not yet formed. An Air Force Hurricane Hunter aircraft is scheduled to visit Harvey’s remnants tomorrow morning, and this could be when Harvey is reclassified as a tropical cyclone.

The model track guidance for ex-Harvey has come into better agreement today, and it appears that a Texas landfall is now the most likely scenario. However, Harvey could stall over Texas for multiple days, and this makes the possibility of flooding a major concern. Over a foot of rain is possible over parts of southeast Texas. Regardless of where Harvey’s center makes landfall, heavy rains are possible from Northeastern Mexico all the way northeast to Western Louisiana, and residents of these areas should begin to prepare and watch the progress of Harvey closely. It is a distinct possibility that Harvey’s center could eventually re-emerge back into the Gulf of Mexico after landfall. The exact future track of Harvey is extremely complicated, and will likely become more definitive when a well-defined center forms. The main threat, as of this time, will be heavy rainfall.

I will be back tomorrow with a more detailed post on Harvey, which is likely to regenerate by that point. There should be a better idea of Harvey’s future track and intensity tomorrow as well.