GaWx

Whereas 2015-6, 1997-8, 1982-3, 1972-3, and 1965-6 were indeed supers with clearly warmer than normal at NYC, the supers 1888-9 and 1877-8 were actually near normal. Are you aware of that? Does that give you some doubt about the NE US torching should this go super?

In the new weeklies, Nino 1+2 warmed from +2.4 back up to +2.7, which ties it with 3-4 weeks ago for the warmest thus far this event. Nino 3.4 remained the same as last week at +0.4. Nino 4 actually cooled slightly from +0.4 to +0.3, while Nino 3 warmed slightly from +0.7 to +0.8. Compared to four weeks ago, Nino 3 warmed 0.6 while Nino 4 is the same.

1. Indeed, if this were to verify, it would be as of August east based (with 1+2 and 3 much warmer than 4) as well as strong in August. How would you expect it to look as it progresses to D, J, and F? 2. Note how warm the global oceans are projected to be as a whole! Less than 5% of the world ocean anomalies are blue while 80%+ are red!

The peak is 0.35 warmer than the prior run, but it does appear to have a warm bias in May.

Good point because I just looked and CAN and especially POAMA have not had anywhere near the warm bias of the Euro. Actually, POAMA looks like it has had no warm bias. Moreover, the latest POAMA (see 1st link below) is consistent with its prior forecast of +2.2 for JAS and has ~+2.5 for ASO while still rising! So, with its lack of warm bias, that's pretty ominous. CANSIPS (see 2nd link below), which appears to have no more than a small warm bias, is slightly warmer than its prior with a trimonthly peak of ~+1.85 (NDJ) vs the prior run's NDJ of +1.73. So, in summary after taking into account biases, whereas the Euro implies a trimonthly peak at strong as most likely (say ~+1.7) and the CANSIPS implies ~~+1.8, the POAMA implies a near alltime record of ~~+2.7! So, still tons of uncertainty and a clear conflict in the models! The Euro has not been too cool since 2004! So, if 2023 ends up again not too cool for the Euro, this POAMA would verify quite a bit too warm as the latest Euro *ignoring its strong warm bias* implies a peak likely only in the low +2s. POAMA: CANSIPS:

1. Unlike the April forecast, which warmed considerably vs March, this May forecast is about the same as April's when comparing the same months. It appears warmer in the animation only because of progression out another month, but each month through October is ~same. This new one still has ASO near +1.8 and SON is ~+1.90-1.95 per eyeballing. 2. As is pointed out in that Twitter thread by a reply from Alvaro (see below), the May Euro forecasts have had a significant warm bias with 2022, 2021, 2020, 2019, and 2017 verifying significantly too warm with only 2018 of the last 6 not being too warm. 2018 verified almost exactly right in May for ASO/SON with forecasts of +0.6/+0.8 vs actuals of +0.5/+0.8. More specifically: - 2022 verified much too warm with a May forecast of -0.29 for SON vs actual of -1.0. - 2021 verified much too warm with a May forecast of -0.02 for SON vs actual of -0.8. - 2020 verified much too warm with a May forecast of -0.37 for SON vs actual of -1.2. - 2019 verified too warm with a May forecast of +0.79 for SON vs actual of +0.3. - 2017 verified way too warm with a May forecast of +0.9 for SON vs actual of -0.7! (worst May bust on record) 3. I can add that 2016 per the Columbia University site verified almost exactly right for ASO/SON with May forecasts of -0.5/-0.5 vs actuals of -0.5/-0.6. 4. 2015 verified a bit too warm with a May forecast of +2.4 for ASO vs actual of +2.2 and a forecast for SON of +2.7 vs actual of +2.4. Note that this 2015 SON forecast issued that May of +2.7 is actually much warmer than the 2023 SON forecast just issued in May of ~+1.9 to +1.95. 5. 2014 verified much too warm with a May forecast of +1.5 for ASO vs actual of only +0.2! 6. 2013 verified very slightly too warm for ASO/SON with May predictions of -0.1 vs actuals of -0.3/-0.2. 7. 2012 verified significantly too warm with May forecasts for ASO/SON of +0.8/+1.0 vs actuals of +0.4/+0.3. 8. 2011 verified significantly too warm with May forecast for ASO of -0.2 vs actual of -0.8. 9. 2010 verified significantly too warm with May forecast for ASO of -0.9 vs actual of -1.6. 10. 2009 verified barely too warm with May forecast for ASO of +0.8 vs actual of +0.7. 11. 2008 verified perfectly with May forecast for ASO of -0.2 vs actual of -0.2. 12. 2007 verified a bit too warm with May forecast for ASO of -0.8 vs actual of -1.1. 13. 2006 verified barely too warm with May forecast for JAS of +0.4 vs actual of +0.3. 14. 2005 verified too warm with May forecast for JAS of +0.4 vs actual of -0.1. 15. 2004 verified barely too cool with May forecast for JAS of +0.5 vs actual of +0.6. So, one has to go all of the way back to 2004 to find the last time the Euro May forecast was too cool for its endpoint and even that was too cool by only 0.1. 16. 2003 verified significantly too cool (last time for that) with May forecast for JAS of -0.4 vs actual of +0.2. 17. 2002 verified a bit too cool with May forecast for ASO of +0.7 vs actual of +1.0. -------------------------------- Summary of Euro May forecasts: - 2022-2005: significantly too warm 10 times, moderately to barely too warm 5 times, correct 3 times, too cool 0 times!! - 2022-2005: average error +0.5! - 2022-2005: average error when actual El Niño verified +0.35 with it correct once, barely too warm twice, moderately too warm once, and way too warm once. For this reason and others, I feel that the chance for a super remains low. I'm favoring high end moderate to strong trimonthly peak (+1.3 to +1.9). - 2004-2002: significantly too cool once, moderately too cool once, barely too cool once. - So, too cool all 3 times 2002-4 but never too cool since 2005! Was the model changed in 2005? Columbia ENSO site: https://iri.columbia.edu/our-expertise/climate/forecasts/enso/

Unlike the April forecast, which warmed considerably vs March, this May forecast is about the same as April's when comparing the same months. It appears warmer in the animation only because of progression out another month, but each month through October is ~same. This new one still has ASO near +1.8 and SON is ~+1.90-1.95 per eyeballing. For this and other reasons, especially the strong warm bias of the Euro (more details about this in next post), I'm keeping chances of super at low with better chance of high end moderate or strong.

The weather has been near ideal from my perspective this week to this point. Much of the last few weeks has been very nice. Today is another great day, but tomorrow will start the increase in dewpoints. It is highly probable that we won't see another extended period similar to this until very late Sept and more likely October. So, I've been taking in every bit of this bonus early springlike period.

I received 2.5-3" of rainfall over the last few days.

Yes, they got it, too. They got 0.7", which like for the other cities mentioned is the latest measurable on record (back to late 1800s). Their high was 45 and low was 33. That high is still the coldest that late in the season.

https://www.weatherbell.com/video/the-saturday-summary-13214956?full

I wouldn't bet against his using the strong 57-58 and 9-10 eventually, but we'll see. Meanwhile, in his continuing fight against recognizing the scientifically proven existence of significant GW from AGW, he did put this out tonight (see Tweet below). He keeps insisting that oceans have warmed from the bottom up via geothermal input rather than from the top down via AGW. He's saying that the atmosphere is warming due to the oceans rather than the reverse meaning he's saying GW is mainly from increased underwater geothermal input. One thing he's failing to recognize is that excess sulfur emissions were likely hiding GW during the 1960s-1970s. Also, if I'm not mistaken, CO2 didn't accelerate markedly until after 1970:

So, BoM has +2.5 for ASO. Though anything's possible, I feel that's way warmer than what will verify then and even probably for the peak. The record high ASO back to 1850 is only +2.2 and just about all other models so far haven't been as warm as this BoM. Plus there tends to be a warm bias overall at this time of year. This will be interesting to follow.

Asheville is another good one to analyze since they get so much more snow on average: - 32 of all 74 seasons (43%) since 1949-50 above their 12.7" mean - A whopping 16 of 26 El Niños (62%) above the 12.7" mean vs - Only 8 of 29 La Niña (28%) vs - 8 of 19 neutral (42%) So, going from La Niña to El Niño more than doubles the chance vs the prior winter for a snowy winter at Asheville. 15 seasons since 1949-50 had 20"+: - 7 of 26 El Niño (27%) - 5 of 19 neutral (26%) - 3 of 29 La Niña (10%) So, the chance for a very snowy winter at Asheville nearly triples from prior winter when going from La Niña to El Niño.

Indeed. Macon is another example. Six of the 26 El Niño seasons since 1950 had above the 1.0" mean. Whereas that's only 23% of them, only 13 of all 74 seasons or only 18% of all since 1949-50 have had above the mean. So, the 23% of El Niño seasons is actually higher than the 15% for other seasons (La Niña and neutral, combined). La Niña really brings it down with only 7%. So, going from La Niña to El Niño more than triples the chance at Macon for an above the mean snow for the season. Neutral is similar to El Niño as is the case for Atlanta.

For much of the SE US, most winters are below the mean. Example: Since 1950, only 1/3 of all seasons had above the mean snowfall at Atlanta. In El Niño seasons, 44% had above the mean snowfall. Whereas that is below 50%, it being well above 33% means El Niños are actually somewhat relatively snowy. Neutral are similar. But La Ninas are much less snowy with only ~20% of Atlanta winters above the mean. Example: This map makes it look like El Niño is a hindrance to snow at Florence, but it isn't at all. So, this map is deceptive for the SE US.

Very little rain in this part of the area. The seabreeze held much of it back. I did hear some loud thunder. The hail just outside Savannah in Richmond Hill, GA, is some of the worst hail in the area in many years, if not decades: https://www.wsav.com/weather-news/hail-rains-down-in-portions-of-chatham-county/amp/ Holy hail! The Melbourne area got hit hard with large hail: https://www.clickorlando.com/weather/2023/04/26/snow-way-hail-covers-i-95-in-florida Hail to this extent and size is very rare in both of these areas.

The Atlanta 1.5" April 25th snow and cold was truly amazing. However, the Atlanta based TWC actually got the year wrong. It was 1910 (same year as the noted Chicago snow), not 1920: https://site.extension.uga.edu/climate/2017/04/april-25-1910-snowfall-in-northern-georgia/#:~:text=From This Day in Weather,of the 30s in April. I've read the old Atlanta newspapers from then (on microfiche at public library) and they predicted for 4/25/1910 rain and warmer than the much colder than normal 4/24. Instead, 4/25 was even colder along with the snow. This snow still is much later in spring than any other measurable snow there on record. Chattanooga was in the same boat except they got 4"! Nashville got 1.5".

No, sorry I don't.

Indeed, the globe and its oceans are warmer overall.

Answer: the latest accumulating snowfall on record for much of the TN Valley and nearby. Nashville got 1.5" on 4/25/1910, which is their latest accumulating snow on record by 15 days (back to 1885)! Chattanooga got an amazing 4.1" that day, which is still their latest accumulating snow on record (back to 1879) by a whopping 17 days! Also, one has to go all of the way back to one full month prior to find as heavy a late season snowstorm (3/25/1971). Their high on 4/25/1910 was a mere 39!

To add to what you said, Atlanta had a high on 4/25/1910 of only 39. After March 26th (going back to 1879), they have had highs below 40 only three times: 39 on 4/3/1987, 36 on 4/5/1891, and 39 on 4/25/1910. So, the 4/25/1910 very cold high really stands out in the record books for how late it is. This accumulating snow so late in April could easily be a once in several hundred year event and could even be a once in a thousand year event. Edit: The old Atlanta newspapers that I read (on microfiche at the public library) and copied forecasted rain and warmer temperatures on April 25th, not snow and colder. April 24th was 18 BN (high of 56 and low of 38) and they thought that that was to be the coldest day of the cold snap. So, this was a big surprise even to the meteorologists!

Does anyone know what happened in your area exactly 113 years ago?

Does anyone here know what happened in Atlanta 113 years ago tomorrow (4/25)?

Today's weekly release (covers last week's mean) has the Nino 1+2 anomaly cooler but only barely. It is still a very impressive +2.5 vs +2.7 the prior two weeks. With only one more full April week left to be reported, this all but assures that this will be the warmest pre El Niño April in 1+2 on record back to 1870, assuming the table that shows the monthlies back to 1870 is going to be based on somewhat similar data. There's often a problem with different tables using different data. So, we'll see later. The more important Nino 3.4 rose from +0.1 to +0.3.