We will get to the forecast in just a second. First, we’ve received a number of questions, asking about the recent “bomb cyclone” and what the heck it means. If you’re an NPR listener, you may catch me discussing exactly that today on Texas Standard.
What is it? A “bomb cyclone” by definition is an area of low pressure (or an “extratropical cyclone”) whose minimum central pressure drops by an average of 1 mb per hour for 24 hours. In other words, it has to drop at least 24 mb over the course of a day or less.
Was this recent storm actually a “bomb cyclone?” Yes. Here are the official surface analysis maps every three hours between 10 PM CT on Wednesday (0300Z) and 1 PM CT on Thursday (1800Z).
Official NWS surface maps from 10 PM Tuesday through 1 PM Wednesday show the storm in the Rockies deepening from about 995 mb to 968 mb, qualifying it as a meteorological “bomb,” or “bomb cyclone.” (National Weather Service)
The storm went from about 995 mb at 10 PM on Tuesday to 968 mb at 1 PM on Wednesday. That’s a 27 mb drop over 15 hours, which allowed this storm to meet the technical definition of a bomb cyclone.
Is bomb cyclone just some fancy new term the media made up to hype weather? Not at all. The term has informally been around since at least the 1940s in Norway (where a lot of modern meteorology has its roots). The technical definition came from a 1980 journal article by MIT meteorology professor Fred Sanders.
So why are we only hearing about it recently? Are these becoming more common? If you catch me on “Texas Standard” today, you’ll hear me say that I believe social media has taken what used to be conversations that only occurred between scientists or super hardcore weather geeks and thrust them into the public square. In other words, instead of these conversations with cool terms like “bomb” or “polar vortex” or “derecho” only occurring in sciencey circles, they’re now occurring in forums where journalists or the public can eavesdrop. I don’t know that these types of storms are necessarily more common in 2019, though that may change in the future. It’s mostly that these terms just accidentally end up out in the wild for everyone to use, rather than only among a select few.
I hope you found this informative! Let’s move on to our forecast.
In the wake of yesterday’s front, look for a mix of clouds and some sunshine early today, though those clouds should thicken up as the day progresses, especially south of I-10. It will be cooler and breezy today, with temperatures likely peaking around 60 degrees or so this afternoon. Some locations will likely struggle to get out of the upper-50s with enough clouds.
A light jacket will be a good accessory tonight, as temperatures will drop back into the middle or upper-50s this evening before the show. Heading home, you’ll see temperatures down into the low- to mid-50s under mostly cloudy skies. A few sprinkles or some drizzle can’t be entirely ruled out.
It won’t be beautiful, but at least a fairly quiet weekend is expected. On Saturday we should see plentiful clouds unfortunately, meaning it will be rather cool. We also can’t entirely rule out some showers or a period of light rain, especially along the coast and south of Houston on Saturday. Sunday’s rain chances should shift even further south toward Matagorda Bay, mostly. I don’t really think rain this weekend will be a big issue if you have outdoor plans, but it’s just something to know may happen.