csnavywx

The jump since '20 has been surprisingly strong. 60-65ZJ just since then.

Plenty warm enough given its location, strength and mode of formation. Not really a factor here. Don't forget that current speeds in the Gulf Stream are on the order of 1 m/s. Only takes a few days in that area to recover from upwelling induced by wind as there's always a fresh supply advected in.

Nino tends to suppress more over the Caribbean and GOM than it does out in the MDR or particularly the subtropical Atlantic. It's just that there's been a big expansion of the 26C isotherm both spatially and at depth over the last 40y (and especially the last few years) in these areas where a Nino won't really help stop development. Obviously if you don't have a mod-strong Nino in place helping shear part of the basin, then this leaves open more area over time to higher SSTs and OHC. ENSO isn't the only game in town though, and changes to static stability via SAL intrusions and the West African Monsoon are important too.

Doh! Poe's Law strikes again!

So, if you were to hand-draw a CONUS surface temperature chart with isotherms, you're telling me that the temperature would go *up* the more stations I have? News to me.

Gonna be wild if we end up breaking Feb '16 with a *September* reading, considering the current Sep. record is about 0.30 below that level.

Sep. already stacking some nuclear daily prints on moyhu. Prob going to end up above Aug at this point. Still 5 or 6 months of prints until ENSO peak.

Some pretty clear SW shear undercutting the outflow this AM on visible sat. Vortex centered skew-Ts show this persisting around the 300mb level for a good 36 hours, so this will likely limit strength until it abates.

Inversion down below 850mb now. Warm core getting very intense.

We'll have to see the dropsonde, but in especially intense TCs with very strong warm cores, the max wind can be under 10kft and have a smaller-than-normal reduction to the surface. (see: Mitch)

He probably just means significantly above the 135 kt threshhold. I mean, if Lee were to reach MPI after the first EWRC, it could get down in the 910s. A 150 kt storm is not impossible with this setup. I'm not calling for that as there can always be unexpected variables, but he probably thinks it will. Yeah, I mean the more reliable guidance is down in the 910s-920s with a superb setup and gargantuan upper level outflow channels, so it checks out. ERCs and a touch of mid-level shear are the biggest "issues".

Ah, the dreaded shrimp. This storm is speedrunning all of the harbingers of a future buzzsaw. Don't love that upstream pattern amplification trend on the latest runs, either.

Trade wind burst pattern looks to resume after a month of relative slumber. Pretty telltale sign in the subsurface that a substantial OKW was generated. This one has more heft to it, so it may break further up the coastline.

I could see why you might think that. In this case however, there's little shear and definitely some banding in the southern semi-circle in the lead-up and during the burst. Edit: A bit of northerly shear and dry air, but nowhere near what Franklin was having to endure during its CCC phase.

If I had to guess, it's evolving more like a pre-satellite era Nino and we're trying to use satellite era data to reference against it. Nothing wrong with that per se, as it's our only reference point, but it's been a good lesson so far in the perils of small sample sizes.

This makes sense so far -- as the warm pool there has not progressed nearly as far as '15 had at this point. It is on the move (finally), as per OSCAR and GODAS (Jul -> Aug). Though I suspect it will be in fits and starts since we're still getting periodic trade surges: Compare to Jul: And GODAS:

For sure -- we're getting close to put-up-or-shut-up time. My lean this year has been at or below average. But it's the type of year where even one or two decent setups can yield some seriously convex risk.

Genuinely hoping none of those pan out. The last thing we need is a TC making into the furnace that is current Gulf/Carrib. SSTs/OHC with low shear this year:

So far, this has been a *very different* evolution than we're used to for a Nino. It's done just fine surviving off of weak OKWs breaking near SA instead of further up the coast and tapping the NE Pac warm pool instead. Once the monsoon ends, we'll probably see the forcing being cited migrate east. The warm pool has already migrated to just west of the dateline and some significant TC-induced cooling has occurred near/north of the Maritime continent. I get the idea that we need strong WWBs and that's the classical analog take, but this one seems hellbent on using a route we haven't seen since the pre-satellite era. If I were a snowbird at this point, I'd be rooting for a HHTH forcing-induced blocking over western NA and to help nudge the BoA low a bit further west of its standard Nino position or just amp the western ridge. Then maybe the supercharged STJ doesn't completely screw over the synoptic setup by flooding the CONUS with Pacific air. Def seems like an easier lift than trying to bank on it heading to a more C-Pac based nino.

Might be relevant: https://journals.ametsoc.org/view/journals/clim/28/22/jcli-d-15-0006.1.xml Paper's a bit dated now but conclusion still holds. Stronger drying from subsidence probably not helping. And whaddya know: Now, I'm sure there was some component of drying from mass deposition from the TC (as Andy points out in the comments), but it was very dry regardless. Most publications will probably cite the stuff we hear all the time (increased SSTs, etc), but being as SSTs are regionally cooler than normal, that wasn't much of a factor here. Gonna say the downsloping helping mix down super dry air aloft was it.

Yep, that's the kicker. The secondary knock-on effects in this case might end up being greater than a simplistic radiative forcing calculation would suggest. And the regional signal for an ensemble is surprisingly large. Large enough that it's a consideration when putting together seasonal forecasts for the next few years. Might -- for instance -- nudge the typical Nino winter/spring pattern of a BoA low further west a bit, blow out snow cover early and chain to more Greenland ridging in the summer. That scenario would certainly match a warmer Arctic and regionally cooler mid-lats and wouldn't shock me if a number of the ensemble members are sniffing out just such a teleconnection. Also, ooof for West Coast rainfall and snowpack if that's correct.

Just got hit by that tail-end charlie cell. Strobing lightning. A few small hailstones but looks like the core thankfully went just south of the house.

Tail-end charlie storm just SW of Fredricksburg looking pretty beastly after that merger.

Yeah, that main bow probably going to steal the show and at the same time close off the (currently) most favorable area for supercells. Cells further south that can remain more discrete will have their shot as they get closer to the Bay.