WxWatcher007

There is prolific rain potential with this one for a lot of areas.

Agree with Tip—I think the limiting factor is time over water and lack of inner core. It’s still not quite organized enough for me to think it immediately takes off after crossing Cuba. If we wanted more wind impacts up here it can’t be rotting over CAE before getting turned northward. It needs to scrape Wilmington to the OBX and get some jet streak assistance as it rolls north. The interesting thing is that regardless the track south the models continue to show it being a potentially prolific rainmaker much further north. If anything that signal has gotten stronger and geographically more expansive.

That solution is unlikely just by virtue of it being a long range (by tropical standards) op run, but you can never count out tropical systems producing prolific rain totals within any 24 hour period, especially if terrain or trough enhancement is possible. Just to illustrate though.. As @ineedsnow notes, there’s the PRE with pretty hellacious convergence and enhancement. Followed up by the event itself The latest Euro abandons its Tennessee odyssey for now and brings it northeast, but aside from a brief heavy rain signal in SNE and Mid-Atlantic it’s OTS before a significant rain event for Atlantic Canada. It’s easy to dismiss these systems around here because it takes a very specific set of circumstances to get meaningful tropical around here, but what makes this increasingly interesting to me at least is 1) the rain signal—this looks like a good PRE candidate even if it stays offshore, and 2) guidance wants to tuck this into the coast—yeah troughs can easily kick these, but the conditions that allow a tropical system to hug the coast northeast also create a larger than climo window for impacts further north. Not always or even often enough to hit (Matthew, Dorian) given inherently hostile climo any time of year, but it seems that once future Debbie misses the initial trough and gets pushed back toward the coast by the ridge and northward with the second trough, there’s a scenario in there where a threat could materialize. At this range I’d still hedge toward a climo kick OTS, but it’s worth a closer eye. This is kind of the scenario I envisioned a few weeks ago for August chances around here. Finally, this is really an eternity away but I was looking at the broader Atlantic environment to do a post about the coming weeks, and noticed that the environment isn’t necessarily a quickly fall apart type for this, especially depending on trough interaction and forward speed. A lot more than you asked for lol but I love this stuff. https://schumacher.atmos.colostate.edu/research/galarneau_etal_2010_mwr.pdf

A lot of changes with the GFS today. Note the trough/ridge in the last three runs. Definitely worth watching with a sharper eye up the coast. Even an inland system in the SE could be very impactful further north.

Pretty big changes on the GFS, which has been leading the way significantly imo. Still an eternity to go in tropical time and a lot to sort out in the steering pattern specifics, but this is increasingly interesting. Note the ridge/trough in the last three runs.

That’d be one hell of a rain event for NE verbatim. Ridge/trough combo gets it done.

00z GFS verbatim brings it right back into the SC coast early Thursday. Still a lot to be resolved with the steering pattern next week. Different time stamp but the GEFS are also further west early on.

But let’s put RI under water?

LFG. Unlikely, but we take the eye candy. That ridge looked better and critically, that trough was deeper.

Clouds developed over my house but not the rain lol.

I’d love to see what the EPS does. The op waffling doesn’t inspire confidence. Also, really good call day ago about this going into the eastern Gulf.

Man the Euro is just a lost cause at this point. Waffling wildly after being consistently wrong early. Hate to see it.

The high to the east helps prevent a quick escape, but troughs are king. That needs a lot of work. I know you know this but it’s not like a wintertime coastal, a BM track won’t cut it for meaningful (non-PRE) impacts around here.

Maybe a closer approach, but like @CoastalWx said the flow isn’t what you need for a more direct shot. Could easily see eastward shifts once there’s a well defined center guidance can effectively model. We watch in case there are changes with the trough but it’s unlikely to change that much right now. The PRE signal has been consistent however, so that’s definitely something to watch for NE and Atlantic Canada.

Aside from 97L, the basin still looks primed for a big peak. Very favorable conditions are lining up as expected.

Totally agree—you can almost always see the threat from range, or at least get a sense that it could trend that way. Isaias is a good example. Henri probably a counter example but fairly quickly I think we could see it was worth watching. I do think the right kind of ridge could theoretically bring some sort of eastern NE tropical threat without much of a classic Midwest trough, but that’d be like threading multiple needles.

Good reference point when looking at 500h

The Euro, which has apparently been lost as of late, delays development until it crosses from the Gulf to SE coastline.

GIPHY or Imgur are great alternatives to allow for posting that doesn’t take up attachment space.

Give it a couple more DC winters

Yeah slow and meandering is not the way to get good tropical up here. Now if that ridge were flexing with the storm off the SE and that trough at D7 were more shallow or better yet wanted to cutoff in the lakes, then it’d be more interesting up here. The most interesting realistic thing for SNE right now is whether this can produce a PRE.

Autumn is our best season. You’ll love it. Winter not so much—especially recently.

Just absolute woodshed the last few seasons. Consistently wrong both the op and ensembles. Not just on the development of the wave but the broader steering pattern itself which is egregious imo at 7-8 days.

The vigorous tropical wave that left Africa days ago is now sharpening and becoming more convectively active as it enters the western Atlantic. The signal on guidance has favored tropical cyclone genesis for days now--much closer to the U.S., and the NHC now designates the area as having 60% odds of development in the next week. Originally, the sprawling wave traversed the eastern and central Atlantic devoid of convection due to the presence of strong SAL. While this prevented convection from developing, a combination of low level moisture pooling, high SSTs/OHC, light wind shear, and diminishing influence of SAL has allowed for gradual disorganized convective development, the first step toward TC genesis that's most likely days from now. https://tropic.ssec.wisc.edu/real-time/mtpw2/product.php?color_type=tpw_nrl_colors&prod=natl&timespan=120hrs&anim=html5 The large wave is now draped across the Greater Antilles, and there are numerous questions over the evolution of the wave in the next 5-7 days. First, how does the wave interaction with the Antilles spur or tighten vorticity? The GFS tried to spawn more robust vorticity after interacting with Haiti/DR, while the Euro for the most part has focused an eventual vortex in the convection that is north of the islands. This obviously has track implications. Second, how does a developing wave take advantage of what is likely to be a favorable upper level environment closer to the US? Does it develop faster, as the Euro until today suggested, and get pulled northward and then kicked OTS or NE by a developing Midwest trough, or, if things are delayed and track into the Gulf as the GFS suggests, where does it go? Third, what will be the steering pattern? There's an increasing signal that the steering pattern between an Atlantic ridge and Midwest trough breaks down as the disturbance reaches the east coast or Gulf, creating immense uncertainty on both track and intensity forecasts. The bottom line is that there's a lot of uncertainty with the forecast ahead. Ensembles are the way to go as we move forward the next few days to get a sense of the envelope of possibilities--which are very broad as it stands. OTS to a Gulf threat are on the table. The Gulf and SE US should watch this closely.

It probably organizes later if the 18z run continued. If anything I think intensity guidance got more aggressive today.