Don't have time for a full update, but here are some thoughts on Ophelia...
It does look to be getting a bit better organized, but this has been the season of satellite signatures being a little bit better than the actual intensity per recon flights (sheared storms excluded). In any case, it'll probably become a tropical storm later today. The center has apparently reformed a bit further to the north, perhaps giving the impression of a distinct NNW motion, though I don't believe this to be the case (at least in the short-term).
Where this storm goes is still up in the air. If this NNW motion actually continues and is not just an artifact of the storm reorganizing, then the whole timetable will need to be moved up a little bit. In terms of development, upper-level winds might become a little bit more favorable in a day or so, but this is only going to marginally be the case. They aren't all that unfavorable now, but the basin is becoming quite crowded in a small area between the low in the Gulf, TD 16, Nate, and Maria with all of the storms influencing the others to a small degree. This makes the potential intensity and track forecasts that much more complicated. Waters are certainly warm enough for some development and largely untapped thus far this season. Thus, the peak intensity likely becomes a function of how long the system stays out over water.
There is a weak mid- to upper-level low currently located just west of Washington D.C.; a ridge is building in from the west, currently extending from Ohio-Tennessee westward to Nebraska-Oklahoma. An upper-level trough is located to the north of this ridge but not making much southward progress at this time. Another weak ridge is trying to build in over the NE US behind the departing trough that has captured Maria, but this will be a transient feature.
The ridge in the central US is showing signs of kicking the weak mid-upper level low out; if this happens and as the storm develops, it would tend to steer the storm more towards the west with time and across Florida into the extreme NE Gulf. If the weakness remains, the storm may start to veer enough to the north so that the trough currently north of the Great Lakes does capture the storm and is enough to keep it near the coast or off-shore of the SE US. These two scenarios sort of mesh with what varying groups of models are doing with the storm, but are quite drastic in the variance between the end-game scenarios.
It is interesting to note that among the ensemble members (http://moe.met.fsu.edu/confidence/), there is very little confidence across the NE US starting in about 2 days and lasting through to 7 days (and likely beyond) as to what happens with this trough as it moves into the NE US. Similarly, there is quite a bit of uncertainty with what the model members do with Ophelia, lingering it around the coastline through the forecast period. While the operational solution shows a general motion towards, say, Charleston, the ensemble members of the model are pretty divided on the motion. This further confirms the spread seen amongst the models.
Nevertheless, if the storm keeps moving more towards the north in the short-term, it'll likely keep doing so. If not, then it'll likely linger around for some time with a Florida landfall more likely in the medium- to long-range. It's one to watch over the next day or so and I think by later on in the day Wednesday, we'll have a better idea of where this one is headed. standard operating procedure for what to do with such divergence in the model guidance is what you are seeing here -- slow motion generally in the middle of the track envelope -- and generally works pretty well. We'll see how it pans out here, but I get the feeling it's not too far off unless the northward "motion"/reformation continues overnight.
More to come as time permits.
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