csnavywx

CI appears likely soon W and SW of DC.

So far, so good. That mass of convection will probably produce a coherent MCV for the region later on today. 

SPC keeping an eye out as well:

Quote

   Another likely influential thunderstorm complex will be ongoing at
   the start of the period across southern IN/OH. In all likelihood one
   or more MCVs will evolve from this activity. These storm-induced
   eddies will likely contribute to further thunderstorm development
   downstream later in the day. Too much uncertainty exists regarding
   these yet-to-develop features to warrant more than low severe
   probabilities. 

New MCS is up and going over OH and IN. Initiation likely in the next few hours over IA. HRRR really pressing this (in the form of an MCV or remnants) as a viable trigger for tomorrow. It looks like the current MCS may track far enough south to prevent it interfering with insolation too much tomorrow morning.

1 minute ago, Stormheartgypsy said:

Good to know and thanks for the info.

Is the ENSO being a neutral position playing into the "fun" weather? Or it strictly how the jet streams wobbles so far north and south and the moisture pumped in the from Gulf?

There tends to be a delay of several months between when an ENSO phase begins and ends and the atmosphere responds. It lags by 2-4 months or so. So, we're still probably feeling some of the effects of the faded Nina. The current drought episode in the West is probably being exacerbated by it (by helping shift the jet north and imparting extra subsidence). Sometimes those effects "spill over" downstream into the Plains.

3 hours ago, Stormheartgypsy said:

Just curious if this drought has to do w/ (possibly) climate change and or the ENSO has moved from what I've read to a neutral (La Nina seems to be over - for now)...

 

Would love some rain here in the MidWest (skip hop away from St Louis)...

Nina years tend to have a higher chance for summer drought but this isn't always a given.

As far as climate change goes, the trend has been for (so far) has been for relatively rapid increases in rainfall and absolute humidity (dewpoint) in the STL area but relatively modest increases in temperature. There's some evidence to strongly suggest this is due to the rapid increase in corn planting area and density, which transpires rapidly and has served to keep temperature increases somewhat muted at the expense of increasing humidity. Since corn and crop land area has reached near its maximum nowadays, I would expect temperature increases to start taking over. If that's the case, the future may include a bit more rainfall on average, but with ever bigger swings between wet and dry. Increasing whiplash or flickering, if you will. Drought sets in and ends quicker, rainfall tends to come in bigger bursts and less towards gentle, soaking rains.

1 hour ago, Kmlwx said:

The 12z GFS has a really nice looking cluster coming through tomorrow around peak heating. It's tough to evaluate how exactly it goes down with the 3 or 6 hour panels. It seems to be on its own right now - would love to see that trend similarly on the CAMs - most look snoozy for now. 

It appears to be a continuation of an overnight MCS that gets going over IA/IL tonight. HRDPS has it too (and the 12km NAM to a lesser extent). It's a possible scenario. HIgh bust potential tonight, though, especially with effectively 3 convective complexes (including the decaying one over OH right now) "in the way" before we get there.

I have a problem with a lot of economic studies and projections concerning climate change because they do not incorporate risk of ruin. The amount of risk and potential damage goes up exponentially with each degree of warming. I think it would be nigh impossible to calculate warmings of 4-6C just because of the non-linearities involved. Even 2-3C could really be stretching it.

It looks like a remnant EML plume gets wrapped in ahead of that front. As long as we can get some forcing strong enough to trigger convective initiation on Sat. afternoon, there will likely be some severe and good parameter space for some evening supercells.

1 hour ago, donsutherland1 said:

On this, we strongly disagree.

Dr. Mann’s revised thinking on what appeared to be a multi-decadal oscillation is a good illustration of how evidence informs scientific conclusions. It is not a defect that undermines climate science. It is testament that climate science is based on evidence and, when the evidence leads to revised conclusions, the conclusions give way to the evidence. That is a far cry from the approach taken by the climate change denial movement where conclusions are built to serve political or ideological ends that are often in direct contradiction to the evidence. 

Dr. Mann’s revised thinking does not, in any way, undermine the scientific understanding of ongoing climate change and its predominant cause. There is currently overwhelming scientific evidence for anthropogenic climate change. Empirical evidence includes warming surface (land and ocean) temperatures, increasing oceanic heat content, ice sheet mass loss, declining Arctic sea ice extent minima, increasing ocean acidification, and measured increases in greenhouse gas forcing. 

As expected from the Greenhouse Effect, the troposphere is warming while the stratosphere is cooling. Consistent with the burning of fossil fuels, which contain the lighter C12 isotope, atmospheric C13 has been falling relative to C12. On account of the dominant role of anthropogenic greenhouse gas forcing, temperature trends can no longer be explained by using only natural forcings. Temperature trends have decoupled from solar irradiance. 

Clear scientific understanding of climate change—what is happening (warming) and why it is happening (anthropogenic greenhouse gas emissions)—now exists. That’s where the debate is finished if one reviews the scientific literature.

Nuances and residual uncertainties remain. The existence of the AMO and its role provided one example. Uncertainties concern feedbacks, potential tipping points, ice sheet evolution, etc. They do not extend to the conclusion that the world is experiencing an ongoing warming event and that increasing greenhouse gas forcing (due to anthropogenic emissions that have created a persistent situation where total emissions > total uptake) is the predominant driver of that warming.

The climate change denial movement has been pushing frames as a substitute for credible scientific work—after all, this anti-science movement possesses no credible alternative explanation for the ongoing warming, even as it bears the burden of proof, if it wants the scientific debate reopened. The most common frames being advanced by the climate change denial movement are targeted at undermining the science through fear, attacks on the science, and exaggeration of uncertainty. These frames include, “climate change is a myth or scare tactic perpetuated by environmentalists, bureaucrats, and political leaders”; “Mainstream climate research is ‘junk’ science”; and, “The scientific evidence for climate change is uncertain” (Dunlap and McCright, 2015).

This 1000 times over. Science is a developmental process, which means you aren't going to always get it right on the first go, or it might need to be adjusted or tossed down the line. In this case, he's refuting his earlier research based on new evidence. That's called updating your priors. The only real failure would be to *not* do this.

Don't sleep on the Monday shortwave. A compact, digging shortwave embedded in NW flow aloft possibly intercepting a plume of moisture and instability fed in ahead of the wave. One of the major questions is timing. A bit earlier and this could easily cause some significant trouble, given the progged shear and instability values progged on the NAM (and trending on the GFS).

3-day total up to 3.21" so far with rain continuing.

All this juice and increasingly dirty ridging is going to make for some decent late afternoon and evening boomers this week.

I find that it's the fructose that comes without the fiber that's the issue. Fruit is fine (unless in excess). HFCS, sucrose and fructose added to foods all tend to pile up and add a lot of load to the liver (since fructose largely can't be absorbed by tissues, unlike glucose -- it has to be processed by the liver), which then partially converts it to lipids that get stored. It's pretty uncanny just how similar ethanol and fructose get processed. The difference is, with ethanol, you eventually get tipsy or drunk and get a signal to stop. With fructose, you don't, and it since it doesn't trigger leptin production in the same way as glucose, the brain doesn't get a signal to stop either. Added sugars are *everywhere* and tough to avoid.

2 hours ago, Bhs1975 said:

Over the long haul as the sun heats up we will need to lower GHG levels to keep Earth habitable but eventually in a billion years or so even 0 GHG levels won't be enough. The Earth completely froze over in the past at least twice because it needed several thousand ppm CO2 to keep that from happening but now with a much hotter Sun that's not the case anymore.

Yeah, that's one of the more academically interesting things about what we've learned so far. During the LGM (and a few glacials before), CO2 approached the lower limit for C3 photosynthesis and despite the cooling, we never came close to freezing over completely. It's probably impossible for the system to do another Snowball episode like it did ~600 Mya as the sun is some 7% brighter now. Another 7% is probably game-over for multi-celled life as the stable climate space in which there's enough CO2 to sustain plant life will disappear. Even in the current era, just the brightening since the PETM and Cretaceous is enough to lower the necessary CO2 to tip into the "hothouse" state by quite a bit. I don't think it would take 1200+ ppm anymore. Maybe 600-800. (This is assuming that the NH and SH act symmetrically, which they almost assuredly do not -- the NH will be hotter sooner). 

16 hours ago, bdgwx said:

 

** Disinformation: Nature has produced 97% of the 400 ppm of CO2 in the atmosphere.

 

 

 

The thing that kills me with this one (that keeps popping up like a zombie) is that none of them have ever come up with a source and then provided evidence for that source. You'd think this would be easy to check. Indeed, if it were coming from the ocean, for instance, you'd expect to see outgassing to the atmosphere and a net flux of CO2 from the surface (and thus an increase in pH over time through the water column). But, instead we see a decrease in pH.

21 hours ago, ChescoWx said:

https://townhall.com/columnists/katiepavlich/2021/05/20/facebook-fact-checkers-punish-and-censor-debate-on-climate-science-n2589647

Let's silence scientist who are not lock step with the narrative.....scary times we live in

It's not a debate when one "side" refuses to acquiesce to any standard of falsifiability. As I've said several times over the years in this forum, I challenge anyone still not convinced by the current theory of the field to state the conditions under which they would change their minds. If you cannot think of a scenario under which you would, then that's faith, not science. If you want to be taken seriously scientifically, then state it. No goalpost moving. It's okay to discard and then amend or re-think your hypothesis after updating your priors. Nobody should fault you for that. However, I (and others) will absolutely fault you if you continue to demand to be taken seriously when you refuse to update your priors and refuse any standard of falsifiability. That's not a "free speech issue", that's a *you* issue. You are free to say whatever you want. We're also free to call you when you state crap. Ignorance is fine, nobody comes into this world fully equipped to deal with it. Willful ignorance is not and shouldn't be. The world is hard enough to deal with without having to sit around and debunk willfully distributed crap all the time.

I know the conditions under which I would change my mind, and so, I'm comfortable with the theory *because* it is falsifiable and it is able to make predictions.

2 hours ago, WxUSAF said:

12z GFS has <0.1” through D10.

This needs to stop soon or feedback will begin to kick in. It's been bizarre watching these high-based TS/shower events over the past few weeks. Looks and feels more like the West with the huge T/Td spreads, inverted V soundings and huge daytime mixing layers -- which have been sneakily depleting water via evapotranspiration while not providing much precip in return.

On 5/4/2021 at 12:25 PM, A-L-E-K said:

denier board shit

It's amazing that after all this time they still exist. Propaganda works. Same tactics as the tobacco companies used to use.

On 5/11/2021 at 6:43 AM, chubbs said:

Climate deniers playing the victim card are the only people I've seen raise the holocaust in a climate discussion.  WSJ the most recent example.

Manufactured aggrievement syndrome. It's rampant nowadays amongst this and similar overlapping groups.

Not totally cooked tomorrow -- yet. There will be subsidence aloft for a good portion of the day and a remnant EML, so it will remain capped to convection for most of the day. Most likely evolution, if it happens, would be initiation over higher terrain and on the leading edge of height falls on the backside of the shortwave ridge.  An old MCV from overnight convection to the west couldn't hurt either. There's ample instability and moderate low-to-mid level shear, so we're just looking for a suitable trigger.

Ripping here now. NW 34G50KT

Showers moving in from the northwest, though most of the precip is evaporating before hitting the ground.

It's high-based shower activity sitting on the top of an inverted-V thermal profile. Much more typical of the West, but in this case, with high gradient winds and a low tropopause. Most of the precip evaporates before hitting the surface, but strong evaporational cooling into a dry-adiabatic sub-cloud layer is able to efficiently mix down winds from aloft.

That TCR value is quite high. 2.6 is on the upper end of most curves, iirc.

3 minutes ago, TimB84 said:

If a mask protects against the flu, wouldn’t it stand to reason that it also protects against covid?

And of course it does. The missing piece of the equation in that post is that flu's natural R is around 1.3. Sars-2 is around 2.5. The variants are 4+. It's much easier to bring that flu number <1 than it is to bring 2.5 or 4 down to <1. That doesn't mean mask mandates aren't working. Anything that slows transmission is effective. It just takes a more than masks for that to happen when the virus you're attempting to screen is this aggressive.

20 hours ago, StormfanaticInd said:

Why is this so hard for Americans to grasp?

Because folks falsely equivocate masks, vaccines and travel restrictions with positive personal freedoms. If the virus infected them and they were the only person it harmed, it would be one thing. However, ignoring all of those things gets others infected, very possibly depriving them of their health, limb or life.

These folks also usually claim to be originalists of the Constitution in some form, but forget that the Founders themselves advocated for quarantines and vaccines (see: Vaccine Act of 1813, for example). Science has advanced much since that time, but I doubt they'd be going against medical doctors, experts and medical science -- they certainly didn't at the time.

We *could* have had something more akin to Australia or New Zealand or South Korea. Instead, we got madness and stupidity. Frankly, I can't hear anyone who wants to try and defend their anti-vaxx, anti-mask, anti-quarantine-measure positions over the pile of over half a million dead Americans. (It will probably be closer to 750k by the time all of the accounting is done properly in a year or two). Remember the Imperial College study early last year? Yeah, I think some people owe a big apology to them on their projections.