The tropics may not be quiet for much longer. Some tropical development is possible next week, but models are not in agreement on which basin will see activity. The Madden-Julian Oscillation (MJO) is currently unfavorable, but both the GFS and CFS models show the MJO becoming more favorable in the Eastern Pacific and Western Atlantic by the week 2 period. The 12z Saturday ECMWF model indicated the possibility of development in the East Pacific about 7-8 days out, while the 00z Sunday GFS run and 18z Saturday NAVGEM run indicated the possibility of an area of low pressure forming in the Northwestern Caribbean Sea during the same timeframe.

On Friday, the American GFS model was somewhat consistent with a tropical cyclone forming in the Northwestern Caribbean Sea. By today’s 00z run, the model had backed off with development somewhat, only showing a broad and elongated area of low pressure in the same area. The GFS model has a history of developing early-season “ghost storms” in the Caribbean Sea, and the NAVGEM is not a reliable model for tropical cyclones. Wind shear remains very high in the Caribbean, and I do not really see any major indications that we will see development there in the near future. In addition, Caribbean development in May is somewhat rare as noted in the previous post. Development in the East Pacific is an alternate possibility, but only the ECMWF has really shown development in that region in the long term. The ECMWF model develops a weak tropical cyclone by 192 hours (8 days), eventually strengthening to a moderate hurricane by 240 hours. The 00z CMC model run has also begun to show development in the East Pacific in the same timeframe.

I do think we could see a tropical cyclone form next week sometime, and I personally think an East Pacific storm is more likely based on climatology and the GFS model’s early season bias of Caribbean tropical cyclone activity. If a named storm forms in the Pacific, it will be named Beatriz, and if a named storm forms in the Atlantic, it will be named Bret. I give a 30% chance of Beatriz forming in the next 10 days, and a 10% chance of Bret forming in the next 10 days. We will have to keep watching the models for several days. I will be back tomorrow for an updated post on this possible system.