I remind everyone interested in synoptic climatology that every ENSO variation has its own character. Most years, news will be blaring about “El Nino means a warm winter”, or mentions that certain parts of the USA will be targeted by either extreme or little precipitation. But this season, the warm equatorial waters of the equatorial Pacific Basin are showing some quirks that you definitely need to follow as you plan your holiday period and the start of 2024.
First and foremost, we continue with a moderate El Nino. Not a “super” or even truly strong event. Secondly, the “typical” aspect is missing in that rather than the usual “pineapple express” pounding southern and central California with a deep tropical moisture fetch, the southern branch heads south into Mexico and Texas. The southern storm track will be better suited to pulling in colder air, as you will find out in the Great Plains, TX and the Mississippi Valley next week. And the week after.
This appears to be a west-based “Modoki: event taking shape, as waters near the Galapagos Islands are cooling. El Nino measures that are strongest in sectors 4 and 3.4 favor colder outcomes in the eastern two-thirds of North America. There is also greater potential for meaningful frozen precipitation. If the numerical models are correct, the current +ENSO will fall apart starting around January 1. While I do not buy the rapid and massive decline shown on the CFS version, I think we reach a neutral state by May 1. Again, if the warming water presence is less off of South America and southeast of Hawaii, we could actually see some meaningful, if not intense, winter weather in January and February. Conversely, my analog forecasts show a very warm spring from the High Plains to the East Coast.
Be watching the cold intrusions in Weeks 2 and 3, which may get in the way of travel and could be accompanied by snow over the Intermountain Region and Upper Midwest. Have a wonderful weekend, everyone! Get ready for the upcoming Thanksgiving!