Spring, Texas – Tropical Storm Nicholas has formed in the Bay of Campeche this morning and the National Hurricane Center has initiated advisories. It is worth noting that the system has organized much earlier than anticipated and will have plenty of time to continue intensifying. On the current forecast track, Nicholas is expected to move north-northwestward through Monday evening which should bring the center very close to Padre Island by 7pm Monday. Thereafter, Nicholas is expected to turn to the North. This is where the models diverge a bit, however landfall is expected somewhere between Matagorda and High Island, TX with models leaning towards the western edge of that zone. As for intensity, Nicholas is currently a Tropical Storm with maximum sustained winds of 40 mph. It is expected to gradually intensify to a strong Tropical Storm with 65 mph sustained winds by Tuesday morning…assuming it remains over water to do so. While it is possible that Nicholas could reach Cat 1 hurricane intensity, it is not currently forecast to do so.
There are several impacts to anticipate with this system, and we’ll start at the coast and work our way inland.
First, nearly the entire Texas coast is under a storm surge watch. Current peak surge forecast by the National Hurricane Center calls for surge of 2-4 feet from Brownsville to High Island, TX including all of Galveston Bay. These surge numbers could increase should Nicholas’ wind field expand rapidly, or if Nicholas intensifies faster than currently forecast. In addition to surge, Nicholas will bring large swells to the offshore waters and big waves inshore. These big waves will increase the risk of coastal flooding and will add to the storm surge to cause significant beach erosion. If you have a coastal home susceptible to surge of 4-6 feet (beachfront homes, canal homes, bay homes, etc.), it is recommend that you begin your storm preparations now. Get sensitive property to higher ground, tie down anything that can blow around or float away, and secure boats appropriately.
We’ll get to winds in a minute, but let’s discuss rainfall. As with all tropical systems, they tend to be prolific rain-makers and Nicholas will be just that. Current rainfall projects indicate that the heaviest rains will fall south of the I-69 corridor in the SE Texas region. Closer to the coast we expect rainfall amounts from 6-10 inches with higher isolated totals possible. Keep in mind that this is in addition to surge, so if you’re in a coastal area that drains poorly anyway, the drainage may be further compromised by storm surge which will allow rainfall to pile-up very quickly to increase overall flooding risk and impacts. In the immediate Houston area, 2-5 inches will be possible…note that these totals could increase or decrease with any westward or eastward shifts in track, respectively. North of Houston, rainfall amounts should be in the 1-4 inch range. We will be keeping a close eye on the track of Tropical Storm Nicholas to see if areas north of the Houston Metro, including Spring, should anticipate higher rainfall totals and flash flooding. A Flash Flood Watch is in effect through Tuesday evening for Harris County and adjacent counties east, west, and south of Harris county, see map below.
Lastly, let’s discuss the wind potential with Tropical Storm Nicholas. Currently Nicholas has sustained winds of 40mph, so he’s a low-end Tropical Storm. The upper air environment is becoming increasingly favorable for intensification and Nicholas is expected to gradually intensify over the next couple of days to become a strong Tropical Storm, and borderline Cat. 1 hurricane. Some things that will could slow the intensification down are:
1) Land interaction – Nicholas could make landfall in south TX and the center could remain over land which would hamper the system’s ability to intensify. However, regardless of land interaction and strength, rainfall and flash flood threat will remain high for SE Texas.
2) Wind shear – Nicholas is currently experiencing some wind shear (change in wind speeds with height) that “tilt” the system and prevent it from strengthening as quickly or at all. This shear is expected to weaken, but not go away completely, which may help prevent Nicholas from reaching hurricane status.
3) Dry air – I don’t know if you noticed, but it felt very Fall-like the past few days with the drier air that came in with a weak cold front. Some of this dry air remains over Texas and Mexico, and could get sucked into the system. This tends to create a very lopsided system with almost no rain on the west half and tons of rain on the east half of the system. This limits intensification as well, and, in this scenario, should the forecast track shift to a landfall near Freeport or Galveston, it is likely Houston and areas north see very little rainfall or wind impacts.
Overall, most of the wind impacts will be confined to the immediate coast and near the center of Tropical Storm Nicholas. Depending on the inland track, Houston area and Spring could experience sustained 20-30 mph winds with some higher gusts in squalls. This translates to winds of 25-35 mph in Houston, and 35-45 mph south of Houston, and even higher along the coast near the landfall point. Wind impacts will vary greatly with storm strength and shifts in track, but trim trees that could pose a danger to property, and secure loose items. Coastal homes should prepare for Cat 1 hurricane winds and gusts, which may lead to some property owners choosing to board up.
Please refer to the key messages from the National Hurricane Center below. Prepare for insanity at your local grocery stores though we hope people will be reasonable with the preparation needs.