After what seems like months of build-up, speculation and watching, Tropical Storm Hermine has finally formed in the Gulf of Mexico. The system still looks somewhat ragged, but its wind speeds have come up, and there’s now the potential for further development before it nears the Florida coast in about 36 hours.
The system has gotten a lot of hype for a mere tropical storm. Part of this is because about a week ago the respected European model really showed strong development (which hasn’t occurred yet), and the fact that it has been nearly three years since a hurricane formed or passed through the Gulf of Mexico. And while this system, formerly known as Invest 99L and Tropical Depression Nine, has been subject to some derision it now should be taken seriously—not only by Florida but much of the east US coast.
Right now this is a big tropical storm, with tropical-storm force winds out to about 100 miles from its center. Those winds may well intensify as the storm has the potential to strengthen into a Category 1 hurricane before landfall, although this is far from certain. Hermine also is both a rain (10-15 inches for some locations of Florida is possible) and surge threat to the west coast of Florida. The National Hurricane Center has these threats covered in its rainfall and storm surge products.
Track models for Tropical Storm Hermine. (Weather Bell)
An upper-level low pressure system is producing heavy rains down the Texas coast, from Corpus Christi to Brownsville, this morning. But Houston is beginning to feel the effects of high pressure, and will continue to do so for the next couple of days. We’ll eventually be cooler, too.
Today and Thursday
The net effect of the high pressure for Houston will be a return to warmer weather for a couple of days. We can’t rule out a few isolated, briefly heavy showers during the afternoon hours, but for the most part we’re going to see partly to mostly sunny skies, and a likely return of temperatures into the mid-90s. It’s what August is supposed to feel like!
Friday and Saturday
By Friday a weak front will backdoor into the region from the northeast. It’s not going to bring brisk winds or much cooler air, alas.
European model depiction of surface winds on Friday morning. (Windyty)
With talk of invests, depressions, tropical storms, and hurricanes (oh my!), readers have asked about some of the science and processes involved with hurricanes. One question we received this week asked us to look at a hurricane’s structure, and where the worst weather occurs.
Infrared satellite imagery of Hurricane Ike before landfall, September 2008 (courtesy NOAA)
It’s been more than two weeks now, but can you remember back to the first part of this month? Very warm nights. Five straight days of 100-degree temperatures. Through the first 13 days of the month, an average high of 99 degrees. Then the big pattern change came, one in which tropical moisture won out over high pressure in August.
A tale of two months. (National Weather Service)
Most of Houston saw cloudy skies, but not too much rain this weekend. But the same cannot be said for some coastal areas, particularly in Matagorda and Brazoria counties. As much as 10 inches fell in the Freeport area, and coastal regions in Matagorda, Brazoria, Galveston and Chambers counties remain under a flash flood watch through at least noon today.
Very heavy rains fell south of Houston, on the coast, on Sunday. (NOAA)
These coastal areas could pick up another couple of inches today as a slow-moving area of low pressure drifts slowly down the Texas coast. While it is not particularly a threat to develop into a tropical system it will remain a rainmaker all the same.
Truth be told, heavy rain is possible for most of the Houston metro area today, as daytime temperatures warm up. Some parts of town could pick up 1-3 inches whereas other areas see threatening skies, but little to no rain. Highs should remain in the upper 80s.
Conditions should dry out some on Tuesday, with less heavy rain, but we’re still likely to see partly cloudy skies, intermittent rain and highs only of about 90 degrees. Don’t look now, but it’s almost the end of August, and fall isn’t too far around the corner.