Common traits of the Rex Block include a relatively zonal flow downstream of the blocking pattern, and this is somewhat evidenced into the central and eastern parts of the nation. The GEFS forecasts (mean of the ensemble members for 00 UTC on 27 June above and 12 UTC on 30 June below) for 500 mb continue the blocking ridge overhead through much of next week. One could use those predictions without alteration, but it is possible to do much better than that through post-processing, a procedure in which numerical forecasts are improved using statistics. The Pacific Decadal Oscillation has soared to near record positive levels making it very difficult to position any type of upper ridge across eastern North America for any significant length of time, even when the ensembles suggest as much. There is widespread discussion today among weather-folks about the low-predictability of the current weather patterns over North America – see Pat Holbrook’s comment on previous post.

We’re going to focus our attention today on the bottom animation, and I will refer frequently back to that bottom panel. The NHC 5-day outlook at bottom indicates the possibility of tropical storm activity west of Mexico by the time the break in ridge occurs. The above animation shows sea surface temperatures across the globe over the last several weeks on the top panel, with anomalies for the same time period on the bottom panel. A lack of defined height anomalies across the Arctic doesn’t help me as far as trying to figure out synoptic temperature trends over the next 48-72 hours. Bering Sea is void of any significant height anomalies, complicating the act of figuring out just what the atmosphere wants to do in the aspect of warm or cold temperature trends in coming days. We first look at the short/medium range forecast, with the American GFS ensembles forecasting 500 millibar height anomalies- the same anomalies as the left-hand panel in the top image. The image above shows snow cover anomalies over the Northern Hemisphere on October 19th. This is the latest we can get these charts, as data outages have lost snow cover records from October 20th to present day.

If you didn’t get what that means, it can be summed up like this: increased storms in the Indian Ocean could prove favorable for those wishing for a warm winter in the eastern 2/3rds of the country. Scroll through the menus until you get to the match you’re betting on. Some of the monasteries are more than thousand years old. ” This followed an earlier tweet that it “wouldn’t be bad to have a little of that good old fashioned Global Warming right now! There has been some gradual warming of surface temperatures in the Indian Ocean over the past few weeks. There is plenty of more in depth reading into Poisson online, but we won’t be delving into that level in this article. I’ll start off right away and say that I think we see this storm either maintain its current position, or even shift south a bit more.

However, if this warming can sustain and flourish in the north Atlantic, the situation could turn more interesting, particularly for winter weather fans in the East US. This may be the most pivotal development in this post, narrowly beating out the Central Pacific warming. This development proves intriguing, as the cold waters stationed near Greenland would have encouraged a positive NAO pattern to develop in the winter, which would be favorable for warm, calm weather in the East US. These changes are proving to be favorable for both another harsh winter, but also a warm winter. We remain a few months away from winter, so there is a lot of time for these factors to change yet again. High levels of industrial pollution and a number of man-induced processes have resulted in climate change. This ridge also allows the formation of a Rex Block in the Western US, with high pressure in the Pacific Northwest opposing low pressure in the Southwest and Southern Plains. Further to the north, massive high pressure acts as a barrier to protect Canada from this closed low and bring a stretch of rather quiet weather to the region. The ridge, with its full length spanning from the northwest Plains to extreme northeast Russia, acts as a barrier between a strong area of low pressure in the northeast Pacific.