Matt Lanza

Summary: We have one final round of rain showers to get through today, although this will be a mere drop in the bucket compared to what fell earlier this week. We then have an extended stretch of dry weather through probably next Thursday or Friday before rain chances re-enter the forecast. Temperatures will be fairly temperate, with a couple cooler days through the period.

Rainfall summary

For Houston, this will officially be at least our 8th wettest January on record. Bush Airport has picked up 8.28″ of rain this month so far. Hobby sits at 7.48″, making it the 6th wettest January. Galveston is at a more meager 5.20″ of rain officially at Scholes Airport, though a rain gauge near The Strand is up over 9 inches this month.

Many larger rivers remain in moderate to even major flood (West Fork of the San Jacinto & Trinity). The National Weather Service has an interactive map with gauges across the region that you can check out for more details.

Today

Watch for some dense fog around the area this morning which could slow you down a bit heading out the door. Otherwise, we will just see clouds through midday. Scattered to numerous showers should crop up this afternoon, after about 1 or 2 PM. The good news is that rain totals are expected to be less than a half-inch and probably closer to a quarter-inch in most cases. Thus, we do not anticipate any flooding concerns today. Showers will exit the area by about midnight or so tonight.

It will be a bit cooler today with highs in the mid-60s, after we hit 71 degrees yesterday officially.

Weekend

Saturday looks like a cooler sort of day with temperatures warming from the low to mid-50s into the upper-50s to low-60s and a good deal of cloud cover. I wouldn’t be shocked to see a few spotty (inconsequential) showers or some light rain for a brief time in spots, especially north and east of Houston. Otherwise, just mostly cloudy.

We dip into the 40s in most spots on Saturday night and Sunday morning before a very nice day Sunday, Sunshine and mid to upper-50s are on the menu.

Monday through Wednesday

Monday will be the coldest morning of this batch of days, with lows in the 30s over a good chunk of the area and around 40 in Houston proper. We’ll have another nice day Monday with sun, some high clouds, and highs in the lower half of the 60s.

Tuesday and Wednesday should see sunshine, although high clouds may spoil that at times. Remember early December, when we had all those spectacular sunsets and an almost permanent deck of cirrus clouds streaming by? We may be setting up in a similar sort of pattern again. Either way, expect highs in the mid-60s Tuesday and upper-60s Wednesday, with lows in the 40s.

Late next week

The pattern begins to change later next week, as another vigorous disturbance emerges out of the Pacific Ocean. This one should crash ashore in California, move through the desert, and emerge over the Southern Plains around next weekend.

The exact intensity, timing, and orientation of this upper level system will determine exactly how significant our rain chances will be. But there is good model agreement on something barging through here next weekend with a round of rain. Ahead of it, probably continued 60s, lows in the 40s and 50s, and perhaps some coastal sea fog.

Summary: A hard freeze is likely north of Houston tonight, while much of the area sees 20s for lows. A light freeze is possible tomorrow night before we warm up. Next week’s rain chances are coming into better focus, with Monday and perhaps Wednesday seeing the most rain, but chances persisting all week long. Localized flooding is something we’ll be watching for, but we’re hopeful the rain is spread out over a long enough period to avoid anything too serious. We’ll have another update on this by Sunday.

Today & Saturday

We’re back at it today, with gusty winds and chilly temperatures, as a second plunge of cold air descends on Texas. This one is much more moderate than the one we saw earlier this week, but still after yesterday’s mid-60s, today’s blustery 40s will feel cold. But, we have the sun, so that counts for something. Winds will be 15 to 25 mph, with gusts to 30 mph, stronger over the water.

In terms of tonight’s freeze, as winds settle and skies remain clear, temps should drop efficiently into the 20s virtually everywhere away from the coast. For the city of Houston and most areas south or east, this will be a light freeze. Northern and western outlying areas are at risk for a brief hard freeze tonight, with lows expected in the mid-20s for The Woodlands, Conroe*, and Brenham. (*Conroe is always an interesting case given that they consistently record the coldest temps in the region, likely due to the location of the airport. So it’s possible they dip into the upper teens tonight)

This will still be about 6 to 10 degrees milder than the hard freeze earlier this week but certainly still capable of hazards to exposed plants (and pets).

Saturday will be breezy and chilly but a little less harsh than Friday. We should see highs in the mid to upper-40s with breezes of 10 to 15 mph or a bit gustier at times. Expect sunshine as well.

Sunday

Expect one more risk of a freeze Sunday morning, mainly north and northeast of Houston. A hard freeze is unlikely anywhere in our area. We will see increasing clouds with a chance of a few showers as early as Sunday afternoon, as high temperatures slow-climb into the low-50s (40s again north).

Next week

The rain we expect next week continues to show up in the forecast rather substantially. We’re starting to hone in on when the worst of it may be now. It looks like we have one pretty strong disturbance that moves through the area on Monday, which should mean numerous to widespread showers and thunderstorms.

This could deliver us anywhere from 1 to 4 inches of rain, and locally higher amounts can’t be ruled out. I would probably say the highest totals may fall to the south and east of Houston, but that is a very low confidence forecast call right now.

Tuesday should see isolated to scattered showers and storms. Rainfall should be a bit more erratic here, with some places seeing a quarter-inch or less and others another 1 to 2 inches perhaps. Then Wednesday may see another strong disturbance with the potential for at least another 1 to 2 inches over a broad area, with higher amounts.

Additional shower chances will follow Thursday and Friday, but it’s tough to say what those look like right now. When all is said and done, the rainfall amounts will tally 3 to 8 inches by Thursday, with higher amounts possible.

Does this mean flooding? It may. With the ground rather firm after this week’s freeze and the subsequent one this weekend, a lot of this water will be quick to run off, which means ponding and street flooding are a good bet in the usual trouble spots. The hope is that the total rainfall will be spread out over a long enough period with enough breaks in between that we avoid any more serious flooding, but it’s something we’ll continue to monitor this weekend. We’re going to especially watch to see how watersheds like Cypress Creek, Spring Creek, the San Jacinto River, and other slower responding basins handle this. This will also impact the Beaumont and Lake Charles areas to some extent. Which location wins the rainfall derby is still TBD.

What about temperatures, you ask? We should see high temperatures well into the 60s most of next week with lows generally in the 50s to low-60s. This may also lead to periods of sea fog on Galveston Island, Bolivar, and along the bays. Maybe some cooler weather resumes by next weekend.

We will have another update for you by Sunday regarding Monday and next week’s rainfall, and I expect we will be implementing our flood scale then as well.

One of the challenges we face as forecasters during Arctic air events is that often times the models are too slow to push in the cold. This type of cold air is shallow and dense (go ahead and insert your jokes here). If you look at a vertical profile of temperatures from Dallas this morning, you can see just how shallow it is. The red line indicates temperature from the surface (bottom of the chart) to the top of the atmosphere. The temperature scale is tilted (skewed) on these atmospheric soundings (called Skew-T plots). But you can see that in Dallas, it was in the teens this morning at the surface. The line that corresponds to “850” on the left says that temperatures were about 34 or 35 degrees at that height, which is about 5,000 feet up. The line skews warmer about halfway there, so the coldest air is only about 2,500 to 3,000 feet deep.

Since the air mass is so shallow, it’s hard sometimes for modeling, particularly the global models we use 3 to 7 days in advance to pick up on how quickly that dense cold air is going to arrive. So based on our experience, we try to account for this by speeding up the arrival time of cold in our forecasts. Every now and then, however, you get a day like today. Temperatures dropped in Houston to about 37 degrees this morning. Meanwhile, as I write this at 3:45 PM, it’s 50 degrees outside. Weren’t we supposed to be cold today? Yes, we had the front stalling at the coast. Instead, it was as warm as 57 in Galveston, 53 at Hobby, 49 at Bush, but only 40 in Conroe and 29 in College Station.

So, the obvious question most of you have is: Does this mean we aren’t getting as cold? No, it does not mean that at all. In fact, very little has changed, forecast-wise today. Once the sun sets, the cold air will resume its southward push, and by tomorrow morning, you can expect temperatures in the 30s in and around Houston and 20s north.

The problem tomorrow is that temperatures will go nowhere. We will stay in the low 30s with some light showers around, and yes that continues to suggest that light icing will be possible. That could begin as early as overnight north and west of Houston, continuing or expanding south and east during the day tomorrow. So, for the Monday holiday, watch for patchy ice north and west in the morning, across the entire area away from the coast during the afternoon and evening. This will not be a widespread major ice storm by any means, but bridges and overpasses will likely have patchy ice across the area tomorrow and tomorrow night, so please exercise extreme caution on the freeways.

I do not want to speculate much at all on Tuesday morning’s commute and school issues right now. That’s above our pay grade, and I would just sort of plan at this point on Tuesday going normally for most folks but have a backup plan in case it does not.

Forecast temperatures are virtually unchanged tonight, tomorrow, and Tuesday into Tuesday night across the area. So we aren’t looking any worse which is good, and this continues to look like a very cold but very manageable event. And if you want warmer thoughts, look no further than the National Blend of Models forecast over the next 10 days. Yes, another freeze is possible this coming weekend, but by all accounts it looks less significant than this first one. But several days in the 60s appear to be in our future. So take solace if you’re too cold.

We’ll have another update for you in the morning!