Beware of the Bowling Ball
Monday, 11:30 a.m.
It has been a while since I regularly bowled. As I changed my life over the past few years, I've picked up other activities that have squeezed that sport largely out of my life. That plus working some during the evenings from home, plus a desire not to get home at 10:00 on a Monday night when I have to get up at 2:15 the next morning made it a far easier decision to not continue in that arena!
If you have ever bowled much, you may have experimented with trying to get the ball to turn as it goes down the lane. One of the reasons you try to throw a 'hook' ball is to change the angle of attack into the pocket, or that area between the head pin and the one adjacent to it to the right (for right handers) or to the left (for lefties). The better angle usually increases the potential of getting a strike on the first ball, which is the object of the game.
How does this relate to the weather? Rather simply, actually. From time to time, we see cut-off lows, or upper-level storms if you will, develop in the atmosphere. These features are so named because they become more or less separated from the main flow of the jet stream. If you look at the upper-level forecast for early Wednesday morning, you can pick out three of these 'closed lows' on the chart:
The one over the Northeast will bring rain, then snow to the Midwest and Great Lakes, with more rain than snow in the Ohio Valley. There will be less rain in the mid-Atlantic states with it, and there will be some snow and ice perhaps changing to rain over the northern interior mid-Atlantic into New England. For the most part, it will be more of a travel impediment than anything else, and what warming takes place ahead of it will be quickly turned back. In fact, the temperature drop in the Midwest and into the Ohio Valley and Great Lakes may well be fast enough that puddles of rain freeze solid before they can fully evaporate, and there may be a small layer of snow on top of that, too.
However, I would like to focus more attention on the one moving into the Southwest late tomorrow and tomorrow night. I reference the closed low and relate it to bowling in that this upper-level storm will more or less 'roll' into the Southwest, across the southern Rockies, then make a hook to the left into the Plains. Here's that same upper-level chart Thursday afternoon:
The storm will essentially have two options. With the downstream upper-level low slowly rolling across New England, the one behind it will either have to slow down and move into the Plains toward the Midwest or redevelop and head more eastward under the downstream feature. Initially, the main or parent storm will take the former option, as you can see from the image above. Eventually, though, with another disturbance likely to rotate through the base of the western trough, as you can see crossing southern California Thursday afternoon, it will be spit out underneath the main upper-level low and head more eastward across the southern tier of states. More on that a little later.
Let me get back to the impact of this storm. Initially, clouds will fan out across Vancouver and British Columbia through the Northwest. Look at the morning infrared image:
This will mean showers in much of these areas, with some snow in the mountains, though little of that moisture will spill over the Cascades into eastern Washington, and almost none of it into eastern Oregon tonight.
However, as a strong upper-level feature streaks southeastward toward the California coast tomorrow, it will not only bring rain inland with it, but it will lower the heights, which translates into lowering snow levels in the Cascades all the way down into the Sierra tomorrow.
By late tomorrow, the rain will be moving into the Los Angeles basin, sweeping into the deserts tomorrow night and Wednesday as it all translates eastward. Furthermore, with the low heights over the interior Northwest and into the Rockies tomorrow night and Wednesday, there will be some snow in these areas. Not necessarily a heavy snow, but snow nonetheless.
Now look at the weather map for late Wednesday:
With that big high up over northwestern Ontario and the low pressure area forming in the lee of the Rockies, it will set up a strong southerly flow of air from the Gulf of Mexico that will cause a rapid moistening of the air mass over the southern and central Plains. Where it's cold enough, that will mean snow starts to break out in parts of northern Kansas and Nebraska back into Colorado. As we go deeper into Wednesday night and Thursday, that may turn out to be a pretty impressive snowfall in parts of Nebraska up into South Dakota and perhaps even Iowa.
In contrast, to the south as the atmosphere becomes more unstable, strong thunderstorms will break out from central Texas into eastern Oklahoma, spreading eastward to the Mississippi Valley Wednesday night into early Thursday. That severe weather threat is likely to carry over into the Tennessee Valley and parts of the Deep South later Thursday and Thursday night.
With the parent storm struggling to break away from the central Plains and Midwest Thursday night into Friday, there will likely be some snow across the Midwest into parts of the Great Lakes. It doesn't look like a blockbuster snowstorm, but it will be enough to cause some travel issues and some delays. As mentioned earlier, this will mean the trailing feature coming into southern California late Thursday will go quietly across the southern Rockies Thursday night. However, as it runs into the back end of the system ahead of it, ostensibly a stalled front, it will cause showers and thunderstorms to re-fire, so to speak, meaning a stormy day Friday across the South and into the Southeast.
All of that from a bowling ball of a storm that forms over California tonight, then rolls across the southern Rockies up into the central Plains and Midwest Thursday into Friday. Check out the latest video on it!
