Tropical Atlantic mostly quiet, for now; TS Olivia forms; WPAC active; US weather
After Hurricane Nadine and tropical storm Oscar died the Atlantic has quieted down. Oscar brought the named storm count to 15, another active year. Since then the Atlantic has relatively quiet. Conditions haven't been all that great for tropical development so we haven't seen much. However things will begin to change as we head into the middle of the month. The environment is somewhat conducive near Florida for the next couple days, right were an area of thunderstorms and showers are. This area has been tagged invest 97L and has been given a 10% chance to develop in the next 48 hours by the NHC. I give 97L a less than 5% chance of development due to the future environment and current structure. 97L has a low pressure but it is not vigorous and there isn't a lot of shower/thunderstorm activity over it. The environment over 97L is expected to deteriorate over the next couple days and 97L probably won't develop into anything noteworthy. The Bahamas and Florida will get some increased rain from 97L and 97L will slowly dissipate.
The GFS model has been showing tropical development for the past couple days. Development could occur as early as in a week. Development would occur in either the Caribbean sea, likely in the western to maybe eastern areas. Runs have varied from a TD/weak TS to a full fledged hurricane and any solution is possible. There will be high TCHP/ SST values and if shear can relax some a named storm can form. The ECMWF model has also has shown the possibility of a developing tropical storm. There is some model support and the MJO should be in the basin so a named storm is very possible. I believe we should be able to squeeze one or two more storms before the season ends. The next few weeks could get pretty interesting before conditions become too hostile.
18z GFS at 384hrs:
12z ECMWF at 240hrs:
Tropical storm Olivia formed yesterday from a quickly organizing tropical wave. The structure of Olivia has continued to improve but at a slower matter. Currently Olivia has 60mph winds, a 998mb pressure, and she is moving NNW at 6mph. The center is firmly under the Central Dense Overcast(CDO) and the center is pretty strongly rotating. However there may be some SW to NE shear impacting Olivia, backed up by the possible tilt of the low-level and mid-level circulation. There is some issues of clarity of the satellite images so it is not known how bad or good the core is. Decent outflow and convection suggest that Olivia could still do a little more strengthening. In the next day higher shear, drier air, and cooler water temperatures should begin to impact Olivia, thus inducing weakening. Olivia will reach a ridge of high pressure and be steered to the WSW in 24-36hrs while weakening. Over the next few days Olivia will turn extra-tropical over the open waters of the eastern Pacific and not affect any landmasses.
Gaemi and Prapiroon
The remnants of Gaemi are still impacting parts of Asia. Rain and some wind were produced when Gaemi made landfall in Vietnam and this is still the case. What is left of Gaemi could reach the Bay of Bengal. It is possible that redevelopment could happen but the circulation is pretty much fading away. I don't think much redevelopment will occur but it is something to watch.
Tropical Storm Prapiroon is really organizing as it churns the Western Pacific. Deep convection is over the center and this convection has became increasingly organized. Banding is clearly evident on satellite and microwave indicates early signs of a possible eyewall. Currently Prapiroon has 50mph(45kt)winds and is moving W at 5mph. Prapiroon has the ingredients to become a powerful typhoon, like others this year. Prapiroon may not become as strong as Jelawat or Sanba but a major hurricane strength typhoon is very possible. No matter what Prapiroon should recurve out to sea before hitting Japan, but we will know more info as we get closer to that time.
A cold few days followed by a warm-up is in store for the US. A freezing cold night is likely in parts of the Midwest and Great Lakes with freeze warnings/frost advisories issued. The growing season will likely becoming to a close soon with these freezing temperatures. Fall colors, on the other hand, are becoming more prominent with the cooler temps. A low pressure system will provide wetter/windier conditions in the eastern third of the nation over the next couple days. After that a ridge will build in providing a warm-up for much of the nation. Temperatures will return to normal to even above normal for many. The east should remain wetter while the west drier with this pattern continuing. Drought conditions will improve in the eastern half of the US while worsening in the western half. No severe weather is expected over the next week with just some garden variety storms in parts of the US. Models show some troughs coming into the northern US in the latter part of the runs after the warm-up. The 12z GFS even showed a snow system moving up the Central US, this is not likely at this time. As we head toward winter temperatures will continue to cool and weather will become more unsettled. All in all the weather shall be fair for a good part of the US over the next few days.
Have a great Monday and I will have a new update Tuesday morning.