TD 2E Threatens Southern Mexico

[malaise]

https://www.wunderground.com/hurricane/eastern-pacific/2017/Tropical-Depression-Two-E

https://www.wunderground.com/cat6/td-2e-threatens-southern-mexico-more-200-killed-sri-lanka-floods
The outlook for 2E: Slow-moving and wet


TD 2E is in a quite supportive environment for growth. Vertical wind shear in the vicinity of 2E should remain very low for at least the next day—no more than around 10 knots (12 mph), as suggested by the 12Z Wednesday run of the SHIPS model. Sea-surface temperatures (SSTs) between 2E and the Mexican coast are close to the average for this time of year, a very warm 29-30°C (84-86°F).

We may have to contend with TD 2E for days to come. Upper-level steering currents are very weak, as suggested by the light wind shear and slow movement. That puts a big asterisk on any particular model solution, because small differences in the model-generated wind field could make a big difference in when (or even whether) 2E comes ashore. In its initial discussion on TD 2E, NHC notes the model discrepancies: GFS, NWRF, and the Canadian model all bring TD 2E onshore on Thursday or Friday, but the ECMWF and UKMET models keep the system languishing offshore. Complex interactions between 2E and the rugged topography near the coast—which are difficult for models to capture—throw even more uncertainty into the track forecast.

Despite the favorable conditions for strengthening, TD 2E hasn’t much time to intensify before it nudges close enough to the Mexican coastline for the topography to interfere with development. The 00Z and 06Z Wednesday runs of the HWRF model—our best model for storm intensity in the 1- to 2-day forecast window—intensify 2E into a higher-end tropical storm before a projected landfall west of Puerto Angel on Thursday afternoon, with top winds of 55-60 knots (62-70 mph). If 2E takes longer to approach the coast, it would have time to strengthen further, although a very slow motion would also churn up cooler water that could dent its strength.