The polar vortex is acting up – January 24, 2024

January 24, 2024Posted inweatherNo Comments

Last month there was some concern that we were having a Sudden Stratospheric Warming Event. It seems that it did happen but in a fairly minor way and the resulting cold intrusions of Arctic air seem to have not lasted for very long. I came across this posted article on Climate.Gov attributed to Laura Cisto and Amy Butler. I am reproducing their article here except for the comments it received. You can access the article with the comments HERE. The comments are always quite interesting and the authors typically reply to those comments. And that process can continue for some time which is why I have provided the link to the Post by Laura Cisto and Amy Butler.

It is difficult reading and not everyone will want to dig into it but it is here for those with a deep interest in weather. Where I have comments, I have put them in boxes within the article. For those with an insatiable curiosity, THIS explanation of Sudden Stratospheric Warming Events will probably quench your thirst.  The blog post that I have in this article describes a recent mini-SSW event that was somewhat unusual.

 

 

To read the full article you may need to click on “Read More”.

NOAA Updates Its Seasonal Outlook on December 21, 2023 – Sudden Stratospheric Warming (SSW) Watch

December 22, 2023Posted inweatherNo Comments

On the third Thursday of the month right on schedule NOAA issued their updated Seasonal Outlook which I describe as their Four-Season Outlook because it extends a bit more than one year into the future. The information released also included the Mid-Month Outlook for the following month plus the weather and drought outlook for the next three months.  I present the information issued by NOAA and try to add context to it. It is quite a challenge for NOAA to address the subsequent month, the subsequent three-month period as well as the twelve successive three-month periods for a year or a bit more.

First, Let’s Take a Look at the (mid-month) Outlook for January.

It will be updated on the last day of December which is soon because the third Thursday of this month occurred at the latest time possible because December 1 the first day of the month was a Monday.

 

Then I present a graphic that shows both the preliminary Outlook for December and the three-month outlook for DJF 2023-2024. So you get the full picture in one graphic. For some, that may be all they are interested in. Others will be interested in the longer-term predictions and also the rationale supporting the predictions which is mostly provided by the NOAA discussion.

The top row is what is now called the Mid-Month Outlook for next month which will be updated at the end of this month. There is a temperature map and a precipitation map. The second row is a three-month outlook that includes next month.  I think the outlook maps are self-explanatory. What is important to remember is that they show deviations from the current definition of normal which is the period 1991 through 2020.  So this is not a forecast of the absolute value of temperature or precipitation but the change from what is defined as normal or to use the technical term “climatology”.

Notice that the outlook for next month and the three-month outlooks are somewhat different, particularly with respect to precipitation.  This tells us that February and March will be different than January to some extent.

The full NOAA Seasonal Outlook extends through January/February/March of 2025. All of these maps are in the body of the article. Large maps are there for January and the three-month period Jan/Feb/Mar.  Small maps are provided beyond that through March of 2025 with a link to get larger versions of these maps.

NOAA provides an excellent discussion to support the maps. It is included in the body of this report. In some cases, one will need to click on “read more” to read the full article.  For those on my email list where I have sent the url of the article, that will not be necessary.

Weather Forecast: Today, Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Five-Day Forecast for the World: posted February 18, 2023

February 17, 2023Posted inweather1 Comment

Updated at 3:30 p.m. EST Saturday, February 18, 2023

Here is what we are paying attention to in the next 48 to 72 hours. The article also includes weather maps for longer-term outlooks and a five-day World weather forecast. The article also provides information on the current Sudden Stratospheric Warming (SSW) Event.

We start with the U.S. Information.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
306 PM EST Sat Feb 18 2023

Valid 00Z Sun Feb 19 2023 – 00Z Tue Feb 21 2023

…Locally heavy snow to spread across the high terrain of the Northern
Rockies and Northwest…

NOAA Updates it’s Four-Season Outlook On February 16, 2023 – Potential El Niño impacts were considered in the outlooks for autumn 2023 and next winter

February 17, 2023Posted inweatherNo Comments

Updated at 3:05 p.m. EST February 17, 2023 to incorporate information on the latest Sudden Stratospheric Warming (SSW) event

On the third Thursday of the month right on schedule NOAA issued what I describe as their Four-Season Outlook. The information released also included the MId-Month Outlook for the single month of March plus the weather and drought outlook for the next three months.  I present the information issued and try to add context to it. It is quite a challenge for NOAA to address the subsequent month, the subsequent three-month period as well as successive three-month periods for a year or a bit more.

It is very useful to read the excellent discussion that NOAA issues with this Seasonal Outlook. The CPC/IRI analysis suggests that ENSO will very soon return to Neutral with a La Nino bias and gradually transition to true Neutral, Neutral with an El Nino bias, and then solidly El Nino. Confidence in the first part of that sequence of transitions is higher than in the latter part of the sequence.