Good morning. A cold front is moving toward the region, and will reach central Houston by around noon, pushing off the coast later this afternoon. I’m not anticipating anything too explosive, but some showers and thunderstorms are possible with the front’s passage. We will see a brief cooldown through Wednesday before we warm up again for the second half of the week. A cold front on Saturday should bring us a more sustained stretch of cooler weather—finally allowing things to feel like winter again out there.

Also, before jumping into the forecast, several readers asked about a string of bright lights in the sky over Houston on Friday evening, at about 6:10 pm CT. I’m sharing a photo from a reader, Dave, below. The passage across the sky took about 1 minute. This was a “train” of Starlink satellites, which are launched in batches of 48 to 60 by SpaceX. The company now has a growing constellation of about 1,700 satellites to provide internet broadband service. The Starlink megaconstellation in low-Earth orbit is celebrated because it will bring high-speed internet to areas without it, but also criticized because orbit-raising trains such as this one impair the ability of astronomers to study the night sky. There are also concerns about orbital debris due to collisions as SpaceX, OneWeb, Amazon, and others assemble such constellations.

Monday

High atmospheric moisture levels are allowing showers to develop south of Interstate 10 this morning, and more scattered showers and thunderstorms are possible. Rain chances will increase as a cold front passes through the area, likely around 10 am for Conroe and The Woodlands, noon for Houston, and afternoon for coastal areas. A line of showers and thunderstorms will accompany the front as it passes through. Most areas will probably see 0.5 inch of rain or less, but a few areas could pick up 1 inch or more. Rains should end pretty quickly after the frontal passage.

After a decidedly humid weekend, temperatures and dewpoints will fall this afternoon, with northerly winds and much drier air. Lows tonight will probably drop to about 50 degrees in Houston, with cooler conditions inland.

Tuesday

Tuesday’s temperatures will depend upon how quickly the clouds clear, but I expect partly to mostly sunny skies by the afternoon hours, with highs in the mid- to upper-60s. With the return of the onshore flow, Tuesday night will probably be 5 to 10 degrees warmer than Monday night.

Wednesday, Thursday, and Friday

A southerly flow really picks back up during the second half of the week, and this will pop temperatures back up into the low 80s by Thursday and Friday. Nights will be correspondingly warm, perhaps not falling below 70 degrees in parts of Houston. Skies will see a mix of sunshine and clouds, with rain chances probably below 10 percent.

Saturday and Sunday

A stronger cold front should arrive on Saturday, probably before noon, to end our fling with warm December weather. Some showers and thunderstorms may accompany this front as well, but at this point I think we’ll see clearing skies by Saturday afternoon, with chilly air moving in overnight, and lows dropping into the 40s. Sunday may only bring highs near 60 degrees, with mostly sunny skies, before a chilly night again. A slow warming trend likely begins Monday.

Hobby Airport has started December with back to back 80 degree days, and there could be more to come. The last time we did back to back 80s in December was in 2019. We also accomplished the feat in 2016, 2015, 2013, and 2012, so it’s not super abnormal. Whatever the case, this is quite a departure from when I last wrote in this space a week ago and we had multiple European model ensemble members depicting 30s for lows in Houston this weekend. You can forget that. Let’s talk about what we can expect.

Today

Look for more fog this morning that should again lift by mid-morning in most spots. Dense Fog Advisories are posted around the region, but the fog is a bit spotty. It appears Brazoria County has some dense, as may parts of Montgomery County. The Beaumont/Port Arthur area is also seeing dense fog. Everyone else seems to be fine or seeing lighter fog. But you may run into some patches of dense fog as you maneuver around the area this morning.

Once the fog lifts, we will be left with a mix of clouds and sun this afternoon, as highs again make a run for 80 degrees. One of the differences between yesterday and today is that we could see a couple sprinkles or showers as a weak disturbance passes by. It may be enough to wet the ground in a few spots, but that’s about all.

Weekend

Saturday will see any morning fog lift once again, leading to a partly to mostly sunny day. A few showers can’t be ruled out Saturday afternoon, but those would be the exception, not the rule. Look for highs in the upper-70s to around 80 degrees after a warm morning in the mid-60s.

Look for mostly the same on Sunday, except it may be more like partly to mostly cloudy. Again, a slight chance of showers will exist, but nothing you need to change plans for I don’t think. Another morning in the mid-60s or warmer will transition to an afternoon in the upper-70s to 80 degrees or so.

Monday

Here’s where some intrigue begins. A cold front should actually press through the region early in the day. We will probably start the day well into the 60s in most spots, and then when the front passes through we will see temps hold or drop a bit. So 80 degrees probably isn’t in the cards for Monday.

Instead, expect a period of morning showers and storms, then cooler, breezy weather in the afternoon. Temperatures should drop into the 50s on Monday night.

Tuesday and beyond

Offshore winds are going to flip around and become onshore winds quickly late Monday night and Tuesday, leading to a substantial increase in moisture. Beyond that, we could be entering a bit of an active period of weather with showers, storms, and even some strong storms in the area ahead of another cold front. This would be most likely later Tuesday or Wednesday. Cooler air would settle in late next week but probably again for only a couple days. By next Saturday, the GFS Ensemble mean already has an over 90% chance that temperature anomalies will be at least 10 degrees warmer than normal.

This means that of the 30+ GFS ensemble members, almost all of them see much above normal temperatures again next weekend.

The Arctic Oscillation

I’m going to take you more under the hood about things right now. Meteorologists use numerous tools to make forecasts. One of those tools is called “teleconnections.” We don’t often talk about those here in an effort not to bore you, but I think it’s instructive today and can explain some of why December looks to be so much different than how autumn has been for the last month or so.

Teleconnections are ways of explaining that because one thing happened in one place, there’s more predictability that something else could happen in another place. In other words, if you have a certain pattern over Alaska, that can often teleconnect to a certain pattern downstream over the continental United States. There are numerous teleconnections we can use, but one of the most useful ones is called the “Arctic Oscillation,” or AO. You can read more about the AO here if you’d like. The simplest explanation? As the AO trends more positive, this indicates a stronger polar vortex, one that’s more likely to stay near the North Pole where it belongs. We typically lean milder in those scenarios with most cold remaining in the high latitudes. If the AO flips significantly negative it can mean the polar vortex has weakened and is more likely to allow chunks of cold to travel south toward the mid-latitudes where more people live. For example, just ahead of the massive February freeze last winter, the AO got as low as -5, which was one of the most negative values of this index recorded since 1950. That did not cause us to get super cold here in Texas, but you bet it helped explain why.

So, why am I telling you about this? Well, if you look at a forecast of the AO Index for the next 2 weeks, what stands out?

It’s raging positive (green line). We are frequently forecast to be at or above +2, with some ensemble members getting as strong as +4 to +5 at times. While this doesn’t guarantee that we’re going to stay warm deep into December, it sure skews the odds that way. No single teleconnection is a magic bullet in meteorology, but they serve as pieces to a larger, complex puzzle we try to solve each day. Today, this one stands out as one that will have an outsized influence on our December weather, so I thought it would be a good time to explain this to you. Hopefully it’s insightful! Enjoy the weekend.

Although we’re in the month of December, you wouldn’t know it from the weather. It’s not that we are going to exactly be hot—rather conditions will remain quite mild—but it’s definitely not going to approach cold weather, even “Houston” cold. The bottom line is that if you’re like Goldilocks, and like things not too hot or not too cold, you’re in luck for at least the next week or 10 days.

Thursday

Dense fog is back across parts of Houston this morning, and a National Weather Service advisory remains in effect until 9 am. After the fog dissipates we should be left partly sunny skies and high temperatures near 80 degrees. The calm winds this morning, which are aiding in the development of fog, should become southerly at 5 to 10 mph this afternoon. Overnight low temperatures will be about five degrees warmer tonight, only dropping into the lower 60s in Houston, with inland areas possibly seeing the upper 50s.

Friday

We’ll likely see the development of more fog on Friday morning. This should be a partly to mostly cloudy day afterward as an atmospheric disturbance passes overhead, but overall rain chances will remain fairly low, probably about 10 percent or so as other factors will mitigate against the development of showers. Highs will likely top out in the upper 70s with another night in the low 60s.

Saturday and Sunday

The weekend continues our trend of mild weather, with highs of around 80 degrees and lows in the lower 60s. Skies on Saturday should be mostly sunny, and although we’ll probably see more clouds on Sunday I think rain chances will remain near zero during the day time. There’s modest chance of light rain Sunday night as a front nears the region.

Next week

The aforementioned front should push into Houston on Monday, probably during the overnight hours but that’s not locked in. This will set the stage for slightly cooler weather for a day or two, with highs on Monday topping out at around 70 degrees, and overnight lows in the 50s. We warm back up before another front (probably) comes through on Wednesday. This one may bring a little rain with it, but beyond that the details are fuzzy. This one probably won’t have too much oomph either, so lows in the 50s seems like a good bet right now.

Good morning and welcome to the first day of winter. Or is it? Meteorologists define the start of winter as Dec. 1, running through the end of February. Then spring starts on March 1, and so on. But there are no hard-and-fast definitions of winter in the Northern Hemisphere. Some people use the winter solstice, which marks the point at which the Sun is the lowest in the sky. That’s reasonable. Still others have more esoteric definitions, as I discovered by reading this fun, unscientific poll recently published by FiveThirtyEight.

I thought we would do something similar here, so I’ve set up a poll for readers to gauge when you think winter begins. If you have some other method of determining the first day of winter, please write it in the comments below. I’ll write a summary post of the results next Monday. I’m genuinely curious what you all think.

One thing is for sure, it won’t feel like winter any time soon here. As we enter December, the overall pattern looks quite mild for the next 10 to 15 days. After this morning, many locations in Houston may not see overnight lows below 50 degrees during the first half of December, and high temperatures will generally be in the 70s. A quick look at the 8-14 day outlook for temperatures from NOAA supports the idea of warmer than normal weather ahead for “winter.” (If you consider early December winter, that is).

Wednesday

As expected, we’re seeing fairly widespread fog this morning, with low temperatures around 50 degrees matching dewpoints. Like we saw on Tuesday, this fog will burn off as the Sun rises and warms the air temperature later this morning. After the fog dissipates we should see mostly sunny skies, with highs generally in the mid- to upper-70s and light southerly winds. Overnight lows will drop into the 50s for Houston.

Thursday and Friday

These will be mild, partly sunny days, with highs in the upper 70s to near 80 degrees, and overnight lows around 60 degrees. Some fog will be possible on both mornings, but otherwise there are no weather concerns.

Saturday and Sunday

The forecast is starting to become a little more clear for the weekend, and generally I think we can expect a mix of sunshine and clouds, with only a slight chance of rain both days. (I’d guess nearly all of the region stays dry, and areas that do see rain will only receive a light mist). Highs will remain in the range of the upper 70s to 80 degrees, with nights around 60 degrees. If you have outdoor plans this weekend, you’re probably safe.

Next week

A weak cool front should arrive on Monday to bring some drier air into the region, and cooler weather. Highs on Monday may peak at about 70 degrees. After a quick warm up, another front appears to be on track for Wednesday. This one may bring a little bit of rain with it, and push nighttime temperatures down into the 50s for a few nights.