A non-tropical low pressure area, designated 95L, is the only area on the NHC’s tracking map worth noting this morning. It is located well out in the subtropical Atlantic, far from land areas. Even though it has gale force winds and some convective activity, it lacks a well organized warm core and is moving over progressively cooler sea surface temperatures. Even if it were to become a subtropical storm, it will continue to move to the northeast and not bother any land areas.
The rest of the tropical Atlantic through the Caribbean Sea and the Gulf of Mexico are, for the most part, nice and quiet. There is a notable increase in convection in the Caribbean which is partly due to the favorable MJO pulse moving through coupled with a tropical wave passing across the region. There is some chance for this energy to eventually develop in the western Gulf of Mexico later this week but I see nothing to suggest a major problem.
In the east Pacific, a large disturbance is moving eastward not far off the coast of Mexico. It has some potential for additional development before moving inland over Mexico later this week, bringing with it more heavy rains for the region.
Hurricane Carlotta made landfall last night along the southern Mexican coastline with winds to near 90 mph, according to the National Hurricane Center. The circulation is now weakening rapidly over the rugged terrain of Mexico but the threat of heavy rains will continue for the next few days. Remember that tropical cyclones release a tremendous amount of heat through rain fall and it takes time for the moisture envelope to totally spin down and dissipate. The mountains of Mexico will also serve as a focusing mechanism to wring out even more moisture and should help to hasten the process. Interests in the region should continue to be aware of the rain threat, especially along the higher elevations where mud slides and flash flooding could occur with little to no warning.
There is another area of interest in the east Pacific but it is farther away from the coast and will likely move in to cooler water before it can develop much.
Now we will turn our attention to the southern and western Gulf of Mexico over the next few days. The pattern is such that there is at leas some potential for a tropical depression to form later next week. Water temps are plenty warm and the current wet phase of the MJO, coupled with the remnants of Carlotta, could trigger a low pressure area to form in the Bay of Campeche. I do not see any indication in the global computer models that anything too strong will come of this but the region will certainly bear watching as we begin the week ahead.
TS Carlotta in the east Pacific
Tropical storm Carlotta is not in any hurry.The fairly slow moving storm continues to edge closer to becoming a hurricane and should do so later today. The NHC forecasts Carlotta to peak at 90 mph – a solid category one hurricane.
For now, the deep convection or thunderstorm activity remains mostly off shore, keeping the wind and precip with it. This could change later today as the forecast track takes the system closer and closer to the coast but without making landfall. This scenario would likely keep the core of the strongest winds off shore but heavy rains and winds to tropical storm force are a good bet for portions of the southern region of Pacific Mexico.
The big concern that I have is the fact that Carlotta is not forecast to move very much after the weekend. Its close proximity to the coast would likely mean a heavy rain event for the region. Interests in the area should be prepared for the possibility of several inches of rain over the next few days which could easily result in flash flooding and mudslides.
Atlantic Basin Quiet
The Atlantic Basin remains nice and quiet with no organized areas of convection noted on satellite imagery. I do not see any evidence that this pattern will change anytime soon although the western Gulf of Mexico could be the place to watch in about a week. Both the GFS and ECMWF models indicate the lowering of pressures across that region as a Monsoon Trough remains in place from the east Pacific, extending eastward in to the western Caribbean and Gulf of Mexico. This focusing mechanism for convection often leads to development though it usually takes several days, similar to what we see in the west Pacific with large areas of low pressure spread out over a wide area. For now, the weekend ahead looks fantastic with no trouble spots at all in the Atlantic, Caribbean or Gulf.
East Pacific Invest Area 94-E
The only area of concern today continues to be invest area 94-E located in the southeast Pacific, just off the coast of Central America. As you can see in the satellite picture (courtesy of the University of Wisconsin’s CIMSS site), the low pressure area is gradually becoming better organized. The red “I” indicates the initial position of the center of the low. There is some banding of the cloud cover and deep tropical convection is maintaining itself. A majority of the reliable computer models indicate that 94-E will move WNW to NW and approach the southeast coast of Mexico in a few days. As far as intensity goes, the SHIPS model indicates category one hurricane strength, assuming that the center does not interact with land. Other intensity models are more conservative, keeping the system a moderate tropical storm at its peak.
The main impact looks to be heavy rain fall for portions of Central America and eventually southeast Mexico. The disturbance is slow moving, so it has time to dump a lot of rain along its path. Interests in the region should be aware of this hazard.
In the Atlantic Basin, things are nice and quiet. It is possible that we may see a window of opportunity for tropical cyclone formation in about a week but the only evidence of that right now is the fact that the MJO phase would be more favorable. This alone does not lead to development- there are plenty of other factors that ultimately drive the genesis of tropical storms and hurricanes. We’ll see what happens as we move towards the latter half of the month. So far, I do not see any consistency in the long range model guidance to suggest development in any location. I’ll post more about 94-E tomorrow morning.
Right on cue, the MJO or Madden-Julian Oscillation, is moving out of the west Pacific and in to the eastern portions of the Pacific. The yellow shading in the graphic indicates the forecast for the MJO from the GFS model over the next several days. The enhanced upward motion associated with the MJO is likely to give birth to a tropical cyclone off the coast of Central America in the southeast Pacific.
The NHC is currently highlighting an area of showers and thunderstorms not too far off of Costa Rica. It has a very pronounced curl to it which indicates to me that development is likely. Water temps are plenty warm and upper level winds will probably just improve over the next few days.
A look at computer models suggests that the system will move rather close to the Pacific coast as it steadily develops. Interests in the region from Costa Rica northwestward to the coast of Mexico should be paying close attention to this feature. At the very least, heavy rain and squally weather will likely impact the immediate coast along the Pacific side of Central America over the next few days. I’ll post more info on this developing system daily with additional updates on our Twitter and Facebook pages as well.