Houston’s pollen season bursts to life as spring takes hold across the region

Good morning. Houston’s forecast continues to hold no concerns weather-wise, with spring-like conditions persisting as far as the eye can see. Of course springtime in Houston also means that our lawns, trees, and flower beds start to emerge from their wintertime slumber. And that means pollen. For now, the major concern comes from our trees—particularly oaks—shedding pollen. According to the City of Houston’s Health Department, tree pollen levels are “extremely heavy” at present, having risen nearly 10-fold over the last week.

(City of Houston Health Department)

This, of course, will pass after a few weeks. But until then expect to feel the effects on your allergies, or in a thin film of yellow-greenish dust on your vehicle or other surfaces outside. This is a small price to pay for summertime shade!

Thursday

Temperatures have generally fallen to about 50 degrees this morning, and we’ll see another sunny day today with highs pushing up to around 70 degrees. You probably won’t notice it too much, but a reinforcing shot of dry air should arrive this afternoon with another moderate front. This will be felt most keenly as winds shift to come from the north-northeast this afternoon. Lows tonight should drop into the 40s with drier air and clear skies.

Friday, Saturday, and Sunday

As high pressure in the wake of this second front dominates our weather, expect fair conditions through the weekend. Each day will see high temperatures of around 80 degrees, with nights mostly in the 50s. Skies will be mostly sunny, with the possible exception of Sunday, which may see a few clouds. Dewpoints will start to rise this weekend as winds turn southerly, but there will be enough dry air both days such that it won’t feel overly humid. So, yeah, this will be a great spring-time weekend.

Here come the 80s! (Weather Bell)

Next week

As the onshore flow gets going, clouds will return next week, along with some modest rain chances by later Tuesday and Wednesday. Highs will remain in the range of 80 degrees, with nights in the 60s. It looks like our next front, a relatively weak one, will arrive later on Wednesday or Thursday, likely dropping lows back into the 50s.

Sunny weather ahead for Houston following Tuesday’s storms

Good morning. Before the forecast, let me just say a few words about Tuesday’s storms. Most of the tornadoes associated with this powerful system remained well to the west (Austin), north (Crockett), and east of the Houston metro area. Notably, a powerful tornado struck the New Orleans area on Tuesday night, killing at least one person, and damaging many homes. Such large tornadoes are relatively rare in cities near the Gulf coast, a category which includes Houston. Why? Because the supercells that produce them typically form and pass further inland. This is due to the sharp temperature gradients needed between warmer and cooler air to produce tornadic rotation, which are often not present so close to the Gulf of Mexico. Usually, but not always, the tornadoes we see in Houston are EF-0 to EF-1, with winds of about 60 to 100 mph. An assessment will be performed today to determine the strength of the New Orleans twister.

There won’t be too many mornings this cold again across Texas, this spring. (Weather Bell)

Wednesday

Temperatures have generally fallen into the upper 40s across the metro area and winds have died down this morning. With high pressure holding sway we’ll see some gorgeous spring weather this week. I call this “almost painful” weather because living in Houston we know the kind of heat and humidity that is coming this summer, and it’s almost painful to think about how pleasant things are now in contrast. But that’s my opinion of course, I know some of my readers absolutely love summers in Houston. To that I say, bless your hearts. High temperatures will reach near 70 degrees today, with winds out of the north at 10 to 15 mph. Low temperatures tonight will be similar, in the upper 40s for most.

Thursday and Friday

We’ll warm up heading toward the end of the work week, with highs in the low 70s on Thursday, and near 80 degrees by Friday. Lows should still drop into the 50s.

Saturday and Sunday

The onshore flow resumes this weekend, but we still should see fairly dry air and mostly sunny skies. In short, it should be another great weekend for whatever springtime activities you have in mind. Both days should see high temperatures of around 80 degrees, give or take. There are no rainfall concerns.

By Sunday highs should rise to the low 80s for much of the region. (Weather Bell)

Next week

Clouds return to the forecast for the first half of next week, but for now I’m not anticipating much in the way of rainfall. Dewpoints will continue to rise, however, so we’ll become friendly with humidity by Monday or Tuesday. The next front should arrive later on Wednesday or next Thursday, but we’ve now reached the point of the forecast where it should be written in pencil, so we’ll just have to see what this way comes.

Strong line of storms will march through Houston this morning at rush hour

The much discussed cold front is advancing toward the Houston metro area, and will push through the region this morning. It is producing a squall line of strong thunderstorms. This line of storms, presently along a line from Victoria-to-Sealy-to-near-The Woodlands, should reach areas such as Sugar Land, Tomball, and downtown Houston by around or before 7 am CT; League City and Baytown by around 8 am, and have exited the area shortly after that.

Houston radar at 5:12 am CT on Tuesday. (RadarScope)

The good news is that, as these storms have moved eastward overnight across Texas, they have lost some of their severity. Therefore, while there remains a chance of hail and tornadoes, that threat should diminish somewhat as the storms moves through our region this morning. Probably the biggest severe weather worry at this point is straight-line wind gusts of 50 or possibly even 60 mph.

HRRR model forecast for radar activity at 7 am CT on Tuesday. (Weather Bell)

The other concern is heavy rainfall as the squall line moves in. Some areas may quickly pick up 2 to 4 inches of rainfall this morning, flooding streets for a short time as high rainfall rates overwhelm roadways. Again, this threat should end quickly as storms exit to the east.

HRRR model forecast for radar activity at 8 am CT, showing the major storms clearing central Houston. (Weather Bell)

Unfortunately, the Houston metro area will be affected this morning as people are heading to work, and children going to school. If it is possible to delay travel until the squall line as passed your area, that would be for the best.

Beginning later this morning, high pressure will ensure that our weather is fair for the remainder of the week, with plenty of sunshine and pleasantly dry air.

Storms will peak overnight as a slow-moving front approaches Houston

Good afternoon. Overall, the forecast remains on track. Houston will experience scattered showers and a few thunderstorms this afternoon and early evening. The threat of severe weather will increase after sunset, and peak overnight, before storms clear the area on Tuesday morning. Let’s examine the dual threats tonight: Severe storms and flooding.

Severe storm potential

NOAA has updated its severe storm outlook for Monday and Monday night, and upgraded some parts of our region to a “moderate” chance of severe storms. This is the second highest level of threat, and is indicative of the potential for supercell thunderstorms. Such storms can produce large hail, strong wind gusts, and tornadoes. The area with the most favorable conditions for these storms later today and tonight is northwest of Houston, and includes Austin and College Station. Most of Houston faces a lesser albeit still notable threat tonight, while the coast is at less of a risk.

Severe storm outlook for Monday and Monday night. (NOAA)

The bottom line is that strong and severe storms are possible tonight in the Houston metro area, particularly after 8 pm and continuing for about a 12-hour period. Not everyone will see severe weather, of course, and we cannot predict precisely where such storms will develop. So be weather aware, and take shelter in the event a tornado warning is issued.

Heavy rainfall potential

Later tonight the potential for heavier, training rainfall will also move into the picture. The problem is that as the cold front nears Houston early Tuesday it will start to slow down. This may cause storms to slow, and thus produce greater accumulations over certain areas. We’re still looking at 1 to 4 inches for most of the area, but bullseyes of 6 inches or more are possible for some locations, especially away from the coast. For this reason we’ve issued a Stage 1 Flood Alert for the metro are north of Interstate 10. Street flooding is possible in these locations.

Excessive rainfall risk for Monday and Monday night. (NOAA)

The good news is that this mess will clear out pretty quickly on Tuesday morning, taking its rainfall off to our east. But it could make for a stormy night, and potentially a messy commute to work on Tuesday morning before that happens.

Matt will have an update for you later this evening.