bdgwx

Reports of thunder snow/sleet are widespread around the St. Louis metro area now.

St. Louis just experienced a very robust band of conditional symmetric instability induced snow. The flakes were were huge and visibilities crashed. This band is moving generally along I-70 in IL right now. Snowfall rates were probably 2-3"/hr.

There is a chance St. Louis might actually get 6"+ out of this storm. It would be the first occurrence in nearly 5 years. It depends on how much of the expected precipitation falls as sleet.

San Juan, PR broke 151 daily max (high + low) records in 2024.

2024 ends as the warmest in the ERA5 period of record. BTW...a lot of atmospheric scientists are moving away from Twitter/X to Bluesky. I'm not sure how to get bsky links to embed or if that's even possible here yet so I'll just post the main link for now. https://bsky.app/profile/climatologist49.bsky.social/post/3lerlgto6y22y

Regarding the MWP...Hubert Lamb, who first identified the MWP, even said he didn't think it was a globally synchronous event. Another related myth is that Michael Mann was trying to hide it. He didn't. His own work corroborated what Lamb and others had already discovered. And it is an especially bizarre myth since Mann was one of the first to hypothesize a cause; what we now call the AMOC. [Lamb 1965] [Mann et al. 2002]

Quoting Tony Heller in an atmospheric science related forum is like quoting Samuel Shenton in an geoscience related forum. Heller's pseudoscience and conspiracy position is so extreme that even one of the most anti-science and conspiracy focused blogs on the internet banned him. It almost defies credulity to believe that either Shenton or Heller genuinely believed the positions they publicly espouse.

The publication cited is [Beaulieu et al. 2024]. They absolutely do NOT say they found no change in the global warming rate since 1970. What they said is that a detectable surge does not meet the statistical significance test using their changepoint modeling methodology...yet. They also outline various warming rates and years at which the warming rate would qualify as a surge with statistical significance. "To detect a warming surge starting in 2010 and ending in 2024, the trend needs to have changed by 84% (equivalent to a trend of 0.034 ∘C/year from 2010–2024). If the time series extends to 2030, the surge would need to change by at least 58% (a magnitude of 0.028 ∘C/year from 2010–2030) to be detectable. If the time series is further extended to 2040, a surge of at least a 39% change (corresponding to a magnitude of 0.026 ∘C/year from 2010–2040) could be detectable." It might be interesting to note that UAH, which the authors did not consider, reports a warming rate of +0.04 C/year from 2010/01 through 2024/10. So the one remaining dataset dataset that many contrarians are still willing to consider does suggest a surge in the warming rate.

I'll remind readers here that ideally we wouldn't remove the UHI effect because it is a real effect. Cities and the land area that they represent really are warmer and really do contribute, albeit only a small amount, to the increase in the global average temperature (GAT). Any removal of the UHI necessarily makes the trend in the GAT lower than it actually is. Ryan Maue's tweet is absurd. Urban areas account for about 3% (at most) of the land area of Earth. Even if you ignore the actual temperature in this 3% portion and instead infill those areas using Kriging or some other local regression technique It's only going to reduce the GAT by a few hundredths of degree C and be biased too low. And keep in mind that the UHI is an anthropogenic source of global warming anyway. If he wants to remove anthropogenic factors from the GAT to make the GAT appear lower than it actually is then he should go all in and remove all anthropogenic factors and not just the UHI effect.

This brings Phoenix's count of daily high records (including both minimum and maximum) to 72 so far in 2024. However, this pales in comparison to San Juan which has reported 141 record highs (including both minimum and maximum) so far in 2024.

Correct. As point of comparison Ian 2022 was $180-210 billion, Harvey 2017 was $190 billion, and Katrina 2005 was $320 billion.

The AccuWeather damage estimate for Milton is $160-180 billion. The revised damage estimate for Helene is $225-250 billion. https://www.accuweather.com/en/hurricane/hurricane-milton-by-the-numbers-an-ef3-tornado-and-blowout-tide/1702670

IKE = Integrated Kinetic Energy. TJ = Terrajoules [Powell & Reinhold 2007] Official Calculator

Per the official 21Z NHC update Milton's IKE has increased dramatically to 78 TJ. For point of comparison using official NHC advisories just prior to landfall... Hurricane Charley 2004 was 12 TJ. Hurricane Helene 2024 was 100 TJ. Hurricane Katrina 2005 was 120 TJ. Superstorm Sandy 2012 was 330 TJ.

Based on the 15Z & 18Z NHC update and the 18Z multiplatform wind field Milton's IKE has decreased to 37 TJ. Since the NHC does not publish the wind fields in their public advisories I can only estimate the IKE. We'll have to wait for the 21Z update for the official value. Anyway, this is good news in that the environment has been more hostile than forecasted in terms of Milton's overall wind field.