WxWatcher007

We finally have stuff worth talking about.

Tropical Overview 8/3 Things have been quiet for most of the season despite three named storms so far. ACE is well below normal, but at this point in the season ACE doesn't really mean much. We have approximately 90% of the season to go, and the peak of the season, which begins around August 20, is right around the corner. There are several factors that have contributed to the quiet start. In recent high activity/hyperactive years, we've seen activity in the tropical Atlantic before climatology makes the region favorable. Think Beryl of last year. That was not the case this year, as a hostile atmospheric pattern, stability, and lower sea surface temperature anomalies (SSTAs) have left the tropical Atlantic devoid of activity, even in the face of historically low Saharan Air Layer intrusions (SAL) during its usual annual peak. Meanwhile, the PAC has been hot. And continues to be so as a favorable phase of the MJO passes through the region. Before more favorable atmospheric conditions move into the Atlantic we are already seeing homebrew starting to percolate off the East Coast. With a favorable MJO in the coming weeks, the window will begin to crack open in the Atlantic. At this time I am tracking three distinct possibilities. (As I wrote this the NHC designated area two as a lemon and area three as an orange) 1. Invest 95L Off the Southeast Coast The first area of interest is already likely in the early TC genesis stage. A current non-tropical low is trying to detach from a frontal boundary off the southeast coast, and is looking more and more like it's trying to become tropical with persistent convection firing now near an apparent center of circulation. This is a very common way to get TC genesis in the homebrew region this time of year. This looks well on its way to developing before conditions become more hostile early in the week. It is not a threat to land, as these frontal system TCs tend to follow the weakness in the trough out to sea. It's interesting, but not overwhelmingly so. 2. "Follow up" Development off Southeast Coast Now this one is much more interesting, and has been for a while now. Yesterday most probably sat up as the happy hour GFS showed a strong system attempt to develop in the wake of 95L off the same frontal boundary, this time getting shunted back into the US. Well, although that run of the GFS was way too aggressive, the signal for some sort of follow up development has been on the guidance for a few days now. It's not terribly hard to see why, as the environment looks at least marginally favorable for some development. Vorticity First--again, the frontal boundary is usually good for getting some vorticity spin up. So if something is far enough off the coast there should be some sort of spin that develops in the coming days. Both models pick up on this in the medium range. This is not enough for TC genesis. Which leads to the second favorable factor. Instability While the tropical Atlantic has been incredibly stable so far this season... There has been no such issue off the East Coast...in fact, instability has been extremely high. What that tells me is that anything that does have spin and can develop an area of low pressure will have a chance to generate convection, which will only help with TC genesis odds as long as the system isn't hugging land the entire time. SSTa Not much analysis needed here. I expect the the southwest Atlantic to be a hotbed of activity this season because that's where the heat is. Any low is going to have a shot with enough time and space to become tropical in this SSTa regime. Shear The key inhibitor here is shear. Often times with these frontal boundary systems near the coast you have shear and drier air that is lurking. That comes with the territory with the frontal boundary. Here it is unclear how favorable a shear environment this potential system will find, but guidance is hinting at a window of lower shear later this week taking hold. What makes this particularly interesting is the steering pattern. While the outcome is different in terms of where the area of vorticity goes, the pattern evolution is the same. In the wake of 95L a ridge builds in and traps whatever could develop along the coast. That's something to legitimately watch. Maybe not closely, yet, but at least with a casual eye. 3. Central Atlantic Wave This final area is highlighted as a lemon (now orange) by the NHC, but the wave hasn't yet left the coast of Africa. This is an area that should benefit from the coming MJO change, and it already has a few things going for it. First, as I mentioned earlier, SAL is at historic lows. Now, that doesn't mean that SAL isn't out in the Atlantic, because it is, but look at the coast of Africa. When this wave comes off, it will likely be in a pocket where there is very little SAL. It will be fighting stability in that part of the basin along with lesser SST anomalies, but that can be manageable with a vigorous enough wave. Timing and location are everything, and this one is still TBD on both. With the steering pattern likely changing with a ridge taking over, if this is able to get trapped under the ridge it will likely be moving into the most favorable conditions for a tropical wave yet this season. Just a little off and it's staying well out to sea. To be sure, I'm not calling for a US threat or anything at this time, but the NHC has a large geographical zone for development for a reason. There is higher than usual uncertainty on where this could develop. This may be our first reasonably strong system of the year for two reasons. First, it is running into the aforementioned warm SW Atlantic. OHC is primed for a system ready to take advantage of it. Even the central Atlantic looks conducive for some strong activity again this year. Second, and potentially far more concerning, is the ensemble guidance that wants to totally wipe out unfavorable shear. This is a fairly stunning retreat of shear by the 00z EPS. So while I'm not necessarily expecting a super burst of activity, we now have plenty to track in advance of the start of peak season, with two areas that are worth watching...

Ok, so normally we wouldn't have threads for current low probability systems, but I guess we're changing that this year. This comes from my bigger overview, which highlights this area of interest. I've been quietly watching for days, and now it's worth discussion. This area of potential has been much more interesting than 95L, and has been for a while now for the reasons below. Yesterday most probably sat up as the happy hour GFS showed a strong system attempt to develop in the wake of 95L off the same frontal boundary, this time getting shunted back into the US. Well, although that run of the GFS was way too aggressive, the signal for some sort of follow up development has been on the guidance for a few days now. It's not terribly hard to see why, as the environment looks at least marginally favorable for some development. Vorticity First--the frontal boundary is usually good for getting some vorticity spin up. This fits with climatology. So if something is far enough off the coast there should be some sort of spin that develops in the coming days. Both models pick up on this in the medium range. This is not enough for TC genesis. Which leads to the second favorable factor. Instability While the tropical Atlantic has been incredibly stable so far this season... There has been no such issue off the East Coast...in fact, instability has been extremely high. What that tells me is that anything that does have spin and can develop an area of low pressure will have a chance to generate convection, which will only help with TC genesis odds as long as the system isn't hugging land the entire time. SSTa Not much analysis needed here. I expect the the southwest Atlantic to be a hotbed of activity this season because that's where the heat is. Any low is going to have a shot with enough time and space to become tropical in this SSTa regime. Shear The key inhibitor here is shear. Often times with these frontal boundary systems near the coast you have shear and drier air that is lurking. That comes with the territory with the frontal boundary. Here it is unclear how favorable a shear environment this potential system will find, but guidance is hinting at a window of lower shear later this week taking hold. What makes this particularly interesting is the steering pattern. While the outcome is different in terms of where the area of vorticity goes, the pattern evolution is the same. In the wake of 95L a ridge builds in and traps whatever could develop along the coast. That's something to legitimately watch. Maybe not closely, yet, but at least with a casual eye.

3.0 in northern NJ https://earthquake.usgs.gov/earthquakes/eventpage/us6000qxsb/executive

Yeah. Slower outcome, warmer water, probably less shear, more time to consolidate, which it would need to have a chance. I agree with that.

This isn’t a way that we get tropical up here, so we’re talking about low odds stuff to begin with. And Chantal aside it’s been hard to get TCG off the EC this year. So it’s worth a casual eye but happy hour is happy hour for a reason.

The boundary off the EC that has allowed the current lemon to develop doesn’t really go anywhere, and it opens the door for a secondary area of vorticity to develop and get trapped along the coast. GFS and Euro have hinted at that potential the last few days but obviously nothing that strong.

I still think 1-2 TCs before August 20, but I’m increasingly bullish for my peak season forecast (again).

He’s not wrong about the general steering potential. A US landfall pattern has been there much of the summer, just haven’t had the activity. Don’t need Webb to see it. Once tropical waves start surviving the trek across the more stable tropical Atlantic and reach the SW Atlantic, there will be landfalls.

https://www.newsweek.com/radioactive-wasps-found-former-south-carolina-nuclear-bomb-site-2106827

Really nice evening out here now.

Get ready.

Yeah, it’s pretty humid out here

Rampant drunkenness in here today lol. Mod excessive rainfall risk extended into SW CT

The PMM on today’s HREF was quite impressive. Interested to see if 00z ramps up.

Somebody tomorrow is getting poured on. I think it’s SW CT into NJ but it’ll be interesting for a bit.

I could use the rain

WPC is tempted to issue a mod risk somewhere in the rainfall zone

Can’t make it up Deleted my duplicate post.

98° at home

We wait for winter to return from its near decade long absence with open arms.

High of 93 at home but I’m in DC the next few days…

Yeah I think we’re far from a lock, but whenever I see a setup like this in the middle of summer it’s worth taking note. The moisture feed looks impressive.

Euro not backing down for Thursday/Friday.