Author: Matt Lanza

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.

Today

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.

Rodeo weather

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.

Weekend

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.

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Late winter whiplash continues into this weekend

Posted by Matt Lanza at 5:44 AM

I’m going to start today’s post with a bit of controversy: February of this year wasn’t that bad of a month when you compare it to February 2018. Believe it or not, 74.3% of all hourly observations in February 2019 had some form of overcast reported. That could be fog, low clouds, high clouds, or even thin clouds with a little sunshine still getting through. But it’s a nice barometer of how cloudy the month was. Guess what? In February 2018, we managed to do 81.9% of all hourly observations in some form of overcast. So as bad as this past month was, it wasn’t quite as cloudy as last year.

February 2019 had some form of overcast almost 75% of the time, which was somehow not as bad as February 2018, which managed that over 80% of the time. (Iowa State University)

February 2019 also ended up with only 1.73″ of rain officially at IAH Airport (Hobby had 3.29″). Last February saw 5.73″ of rain officially. So despite our many days of rain this year, it was actually wetter last year. But last February averaged 62.5°, while this February averaged 59.7°. So I’m giving the edge to this February for being the worse of the two months on the colder weather alone.

Today

Whatever the case, February is in the rear view mirror, and it is now onto March, which will come in….as February ended. Expect a lot of low, dreary cloud cover today. Showers are possible, but not likely. More likely will be patches of drizzle at times.

Temperatures will be the challenging part of the forecast today. That cold front from yesterday was supposed to return back north today as a warm front. That appears to not be the case, so expect a mostly chilly start to the month today. Model guidance says we will get into the low- to mid-60s later today. Given our starting point this morning in the mid-40s, I would not be shocked to see us struggle to get into the upper-50s by evening and then continue a slow rise to near 60° tonight. Either way, we’ll get there. It’s just a matter of whether it’s today, tonight, or Saturday morning.

Rodeo weather


I think we are in good shape for the rodeo tonight in terms of rain chances. Yes, I cannot entirely promise there will not be a shower, but I think that would be rather unlikely. Temperatures are another matter. Expect mostly cloudy and cool, damp conditions. Temperatures will probably be about 56-59° in the early evening and post-show temperatures should be, well, in the 56-59° range. Temps won’t move much during the evening. Watch for areas of patchy fog on your drive home, especially if you’re heading southeast of town.

Saturday

I don’t expect much serious weather Saturday, aside from areas of dense sea fog developing once again. Coastal and Bay Area communities will likely be plagued by fog once again late tomorrow and tomorrow night. The rest of us should see mostly clouds, again, though a few scattered showers will be possible through the day, especially along or north of I-10. Temperatures will continue to be difficult. South of I-10 stands the best chance at being quite warm tomorrow with highs near 75° or so. Those chances of warmth get smaller as you go north. Some places north of I-10 tomorrow may not get above the low- to mid-60s. It’s possible that at some point tomorrow Conroe is around 60°, while Pearland is sitting at 76°. It will be that kind of day.

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Clearing up through the weekend

Posted by Matt Lanza at 5:48 AM

The good news is that the worst of the weather the next couple days will likely miss the Houston area well to the northeast. The bad news is that we will still have multiple rain chances to contend with through tomorrow before we get on to the good stuff.

Today

While today should not be a washout, there will be plenty of shower activity around. Initially, showers are west of Houston near Katy and north up through Conroe.

Radar this morning shows most shower activity from about Katy north through Tomball and into Conroe. (RadarScope)

As we go into this afternoon, I think we’ll see the focus of these showers shift east of I-45 and north of I-10. Thunderstorms will also be possible, but with the area likely to see some degree of atmospheric capping (“the cap,” as it’s often referred to, which is basically an atmospheric temperature inversion that inhibits thunderstorm growth) I don’t think we will see too much in the way of significant storms. That will be reserved for areas well north of Houston, up toward the ArkLaTex.

Yesterday was cold and drizzly. Today will begin similarly. We should see temps warm a bit further today though and manage at least the upper-60s in Houston, mid-60s in The Woodlands, and low-60s in the Brazos Valley. That being said, sometimes temperatures behave very stubbornly in these types of patterns, so there’s a definite slight chance we don’t get out of the 50s until later tonight. Keep the jacket handy.

For at least the 500th* time this month, fog is pestering the coast this morning once again.
*approximate

Dense fog is an issue along the coast and in the bays, so give yourself extra time if you are traveling to or from those areas today. (NWS Houston)

Dense fog is likely to hang along the coast and in the bays most of the day today. Exercise caution if you’ll be driving to or from those areas today.

Tonight

We will carry a continued chance of showers through the night, but no heavy activity is expected. It may be more mist or drizzle than anything, with a gradual transition toward showers. Fog will continue in the bays and along the coast, though it could begin to become a little more dispersed at times overnight as winds pick up a bit. Look for temperatures to hold steady or finally rise into the mid- to upper-60s if they haven’t gotten there this afternoon.

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Soon heading back in the clouds for a little while

Posted by Matt Lanza at 5:43 AM

We are heading back to being mired in a weather pattern that is generally low impact (aside from some fog) but also fairly obnoxious: Lots of clouds, cold fronts that will shift temperatures in a big way depending on where they’re situated, and plenty of rain chances but ultimately not a lot of rain accumulation. Let’s dive in.

Today

Areas of fog, locally dense, have developed this morning, and there is a Dense Fog Advisory through 9 AM for most of the area. Give yourself a couple extra minutes out the door today. As fog lifts, expect a good deal of cloud cover this morning, giving way to some partial afternoon sunshine at times. High temperatures today will be contingent on sunshine. With a lot of sun, we could make a run for 80° in spots, particularly west of I-45. With clouds hanging on, expect upper-70s in most places. Some fog may roll back into coastal communities later this afternoon.

Saturday

The forecast for tomorrow is tricky. The first in a series of cold fronts will get down to about US-59 in the morning.

You can clearly see Saturday’s cold front when looking at forecast dewpoints from the NAM model. It’s basically along US-59 at 7 AM. (Weather Bell)

Using the image above (which shows dewpoints instead of air temperatures), you can see the cold front is conveniently right along US-59. This is from the NAM model, which is probably the most aggressive of the models in bringing this front south. In fact, this may even be a smidge too far south and east. But I want to show you how sharp a cutoff this is between very warm humid and potentially cooler and drier.

The front will likely make limited progress south and may even begin to retreat a bit back to the north in the afternoon. Ahead of the front, we will see areas of dense fog along the coast or in the bays once again for much of tomorrow. Temperatures will likely be in the 70s to perhaps near 80° again. North and west of Houston closer to the front in the afternoon, look for mid-70s. There is a small degree of uncertainty tomorrow. If the front is able to be aggressive and dives southeast enough, some areas north or west of US-59 may only see highs in the 60s Saturday.

The good news is that rain chances look limited on Saturday. There may be a few showers or sprinkles along the coast, but otherwise, it just looks mostly cloudy tomorrow (foggy along the coast).

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