The big warm anomaly we looked at yesterday is still there, and is now being fortified by a third major stream of high-flying PWAT having a source in the South China Sea. The anomaly’s hottest spot, up about 20C, is even larger today. If you are opening this site today you can check it out, but I want to move on to some things that are just as interesting, involving the peculiar hole shape that has formed in the center of the Arctic Ocean. There has been an absolute explosion of the northern polar vortex, leaving the normal 500hPa air pressure pattern completely scrambled, with the relatively elevated hole feature sitting in the center. This is how the entire setup now looks from within the Weather Map site, https://climatereanalyzer.org/wx/DailySummary/#t2.
If you compare this pattern with the more usual shape of the broad vortex region as seen in the south, which remains highly unified, the contrast is stark, leaving the hole in the north begging for an explanation. The image of it shown yesterday on the Jetstream map, where it appears in the shape of a doughnut, is about the same today. There is one thing we can learn about it that is most unusual, namely, the cyclonic jet wind blowing around it is moving in a clockwise direction—not at all normal for any jetstream wind in the northern hemisphere. All of the multiple thick green outlines you see on this map (usually there is just one of these, and much larger) are hosts to separate strong jetstream pathways that are running regular counter-clockwise routes as they circle their low-elevation interiors. The interior thin light-blue lines are still acting as hosts to their own set of jetstream pathways, and these also maintain a regular counter-clockwise movement following the overall breakup.
Now we need to inquire into the cause of a big warming anomaly observed within and around this central hole, (second map down). All I can think of is that the greenhouse effect from one or more PWAT streams must somehow be in play. If you look closely at the above image you can see that there are four possible entry points where PWAT streams might be able to sneak in between any two of the four large zones enclosed by thick green rings. I believe the tail ends of two such streams have managed to do so, and that one of these has its origins in the Gulf of Mexico! Let’s take a look:
From what I can see, the stream that emerges from the Gulf (which has first passed the requirements of warm water and clear sky) heads north through Texas to Montana, turns left, then right, where it gets a boost merging in from the west, up along the coast and over Alaska, has another boost in the Bering Strait area, then to the right around the far coast of the Arctic Ocean where it forms a tight circle while adding still more water that mixes in from beyond. The amount of water introduced in this way is relatively large, peaking at 12-13kg in spots, and well-enough distributed to enable the broad anomaly area that ends up like this:
One final remark. As you can see in the two charts above, the heavy PWAT stream from the Gulf is leaving a trail of anomalous cooling as it crosses a broad section of the United States, an apparent contradiction of everything I’ve been saying in these letters. I can see two good reasons that serve to offset the expected warming. One is that the entire area is barely emerging from a full week of strong cooling due to overhead PWAT streaming being blocked by conditions just now being shifted aside to the north, where they remain in effect. This long and unusual siege has left the ground unnaturally cold and quite unable to provide the usual amount of radiation that would ordinarily be feeding lots of energy into the local greenhouse operation at this time of year. The other is that heavy clouding and rainfall following the cold spell has provided an albedo effect that prevents sunshine from reaching the surface and warming up the air as well as the ground again during the day. One more map is needed to show the tracking effect of this very wet stream:
Carl