Conditions are quite a bit warmer across the metro area this morning, with most of the region somewhere in the 50s. Our forecast remains much the same as it’s been—with unsettled weather for a day or so, breezy weather, and then clearing conditions for what should be an excellent December weekend.
Wednesday
Today will be warm-ish for mid-December, with highs in the upper 60s under cloudy skies. Steady, southerly winds will bring the humidity, and also be pushing up moisture levels that will boost rain chances during the overnight hours. Although some light showers are possible Wednesday afternoon and evening, most high-resolution models hold off any stronger storms until later Wednesday night and Thursday morning.
Thursday morning
As an upper-level disturbance moves in from the west, and a cold front barrels down from the northwest, it now appears as though a fairly robust line of showers will move through southeast Texas on Thursday morning, roughly from around 2am through 8am.
Rain accumulations should be greater to the east of Houston. (National Weather Service)
This line of storms doesn’t look too severe—although some thunderstorms are possible—but showers should be heavy enough to drop 1 to 2 inches of rainfall on their way through the area. Fortunately the storms should make fairly steady progress and not linger too long.
Another cold and frosty morning for the region, with a light freeze for areas north of Houston, including Conroe and Huntsville, and mid- to upper-30s in the city itself. We’ll now see a moderate warming trend through Thursday, before another (quite blustery, as it turns out) front pushes into the area. This weekend looks spectacular for December—especially Sunday.
Observed temperatures at 6 a.m. Tuesday. (National Weather Service)
Tuesday
After the chilly start today, we should warm into the lower or even mid-60s under mostly sunny skies. A wind shift to the southeast will aid in the warm-up, and this onshore flow will also keep temperatures tonight a good 10 to 15 degrees warmer than Monday night. Skies turn partly cloudy tonight.
Wednesday
As the onshore flow does its thing, we’ll see a corresponding increase in moisture levels, and our partly cloudy skies will become mostly cloudy. This should limit highs to the upper-60s during the daytime, and we likely won’t see much of a cooldown during the evening hours. Some light showers will be possible later during the afternoon or evening, but probably will hold off until later.
After an oh-so-gray weekend, skies have finally cleared out overnight and this has allowed temperatures to fall to near-freezing north of Houston, into the upper 30s for most of the city, and mid-40s along the coast. With light northwesterly winds out there, it’s quite cold this morning.
Monday
High pressure will dominate our weather today, and although skies will be mostly sunny, temperatures probably won’t rise much out of the mid-50s. Low temperatures on Monday night should be similar to Sunday night, so it will be another one for fireplaces and heaters.
Expect another chilly night on Monday night. (National Weather Service)
Tuesday
This should be another sunny day, and start out a lot like Monday. However, as high pressure moves off, winds will return from the south or southeast later in the day, and this should moderate overnight temperatures. Lows Tuesday night probably will not fall below 50 degrees as the warmer Gulf of Mexico air mass exerts its influence.
Good morning, and I hope we all managed okay overnight. The worst of the rain is long past, though we will still have rain chances for a few more hours this morning. Then, we are just setup for a chilly weekend. Let’s walk through things here.
This morning
Radar as of 6:20 this morning shows sporadic showers across the region, with heavier rain marching east into Louisiana. We have one additional batch of heavy rain that stretches from near Victoria southwest to Beeville down in South Texas.
Radar as of 6:25 AM showed one final batch of moderate to heavy rain poised to move into the southeastern half of the Houston area this morning. (Radarscope)
This batch of showers will push through the southeast half of the Houston area over the next 2-3 hours. Once that clears, steady rain should end. I can’t rule out lingering light rain or drizzle the rest of today. But the risk for moderate to heavy rain ends with this last batch pushing through.
Travel
As of 6:45 this morning, there were just shy of 20 high water locations on area roadways indicated by Houston TranStar
Houston TranStar maps showed about 20 high water locations, dispersed throughout the area, as indicated by little water droplets on the map here. (Houston TranStar)
The high water locations are pretty evenly dispersed across the region. If you’re out and about early this morning, just keep that in mind and drive carefully. Never go around barricades.
Flooding
Overnight, we saw Keegans Bayou, Halls Bayou, Greens Bayou, Armand Bayou, Little Cypress Creek, and South Mayde Creek come out of their banks. As of 6 AM, several were still out of banks or at bankfull and slowly receding. Cypress Creek, Spring Creek, and Cedar Bayou are all rising but expected to stay within their banks.
The exception to this will be the West Fork of the San Jacinto River.
The West Fork of the San Jacinto River at Humble is heading into major flood stage and will stay there for a few days. (National Weather Service)
Because of heavy upstream rains and heavy rains in the area, all that runoff is filtering into the San Jacinto River, and it is expected to crest sometime by Monday or Tuesday in major flood stage at Humble. With the forecast of a 53.9 foot crest, major lowland flooding is expected with several subdivisions impacted. You can see the expected impacts at each level on the NWS website for this particular gage. For reference, this particular location crested just shy of 51.7 feet back in March. So this will be a bit higher.
Rain Totals
Houston officially had 4.31″ of rain on Friday, making December 7, 2018 the 5th wettest December day on record in the city, going back to the late 1800s. It was also our wettest single day since August of 2017, which we all know was during Hurricane Harvey.
Per the Harris County Flood Control website, most of the Houston area received essentially what was forecast. Most places saw 3-5″ of rain, with a few spots seeing more.
Total rainfall seemed to average around 4-5″ in most of Harris County, with a few spots seeing near or over 6″, and a few others seeing 3-4″ or less. (Harris County Flood Control)
With rain totals like this, it’s never how much falls, it’s how much of it falls quickly that really matters and is always the challenge for us in forecasting. Hopefully we made that clear in the runup to this storm. Fortunately, we’ve now got a few days to dry out, with our next rain chance not in the forecast until at least Wednesday night or Thursday.
