An omega block is so called because the upper air pattern resembles that of the Greek letter “omega”, as shown below. With these patterns, you can normally experience extremes (not all cases, but if this is summer we’ll talk about record temperatures and the problems associated with them). hot sun) because this pattern becomes simply stuck.
We see verbatim this week across the US, two common trenches on both coasts while a major ridge lies south of Canada and above-average elevations are mostly confined to the Midwest.
Using the 5-day temperature anomaly description, you can easily determine the location of the trenches on both the coast and the mid-mountain by the relationship to the temperature. Below-average elevations correspond to lower temperatures, and vice versa, this same pattern would lead to flood concerns across the Intermountain West and Great Basin by exacerbating heat-induced snowmelt warmer .
Furthermore, thanks to the high pressure “clamping” in between both upper lows, you can see where the most activity and turbulence is happening, which is interesting to watch the two cyclonic circulations continue in when it comes to the Midwest and the Plains, there’s a complete lack of them or even any rainfall for that matter.
The good news is that by the 2nd week of May, this current meridian elevation pattern becomes “unstable” as the band extends over most of CONUS, with the eastern trough pushing out into the Atlantic while the trough extends over most of CONUS. The West Bank pulls away. An active southerly jet stream looks set to occur, potentially bringing more extreme weather events, which also become absent in the omega blocks and of course that could certainly be a thing. Good. However, we do see omega blocks appearing randomly and especially during the transitional seasons as wavelengths become shorter as we approach the summer months.
About the author
Hello! My name is Armando Salvadore and I am a Mississippi State graduate with a Bachelor of Professional Meteorology and an Activity Meteorologist working in the Private Sector. Stay tuned if you like technical, exotic, and general weather tweets! Also big on long-range forecasting as well! Twitter: @KaptMands