Southeast Texas still in a drought

The heavy rain from Hurricane Dolly last week eased the drought in far south Texas, but we didn't get enough rain around here.

A survey of soil moisture and drought conditions across the state still shows most of southeast Texas is moderately or extremely dry.

As of July 31, rainfall for the year is about seven inches below normal in Houston and almost ten inches below normal in Galveston. Every month since March has ended drier than normal at Bush Intercontinental Airport.

Hurricane season heats up in August

Although the month of July brought us a category 2 hurricane, this month is not usually a busy month in the tropics. A track of all hurricanes that have developed during the month of July over the last 100 years shows only a few dozen cyclones scattered throughout the Atlantic basin.

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Now, compare that with a map showing all the August hurricanes that have developed over the past 100 years. Climatologically, August is the beginning of the most active time of the hurricane season. The peak of the season is in mid-September. Hurricane season usually winds down by early October. 

Some of the most infamous hurricanes made landfall during the month of August. Hurricane Camille was a category 5 storm that slammed into Louisiana and Mississippi in 1969. Hurricane Alicia developed in 1983, twenty five years ago, in late August. Hurricane Andrew, another category 5 hurricane, roared into south Florida in August 1992. Hurricane Bret made landfall in south Texas in August 1999. And then there was Hurricane Katrina in 2005.

Last week we were tracking three different tropical systems at the same time. The tropics are quiet right now. But if history is any indication of what's ahead, watch for tropical systems to develop very quickly over the next several weeks.

Satellite shows flooding from Hurricane Dolly

Sensors on NASA's Aqua satellite picked up the flooding caused by Hurricane Dolly last week.  Up to a foot of rain fell in some parts of south Texas where the eye made landfall. Many roads and streets, fields and yards were flooded by the heavy, tropical showers.

In the image to the left, vegetation is green and the water is dark blue and black. Flooding was reported around Brownsville, along South Padre Island and throughout the counties near the Rio Grande River. Flooding is also evident in northern Mexico.

The eye of Hurricane Dolly tracked parallel to the coast for several hours. The high winds and torrential rain scoured the west side of South Padre Island. This actually altered the shape the island as seen by satellite.

Even though flooding occurred in many spots, the Rio Grande River stayed below floodstage in the days following the hurricane.

Hurricane Dolly: From Drought to Deluge

The moisture from Hurricane Dolly quickly erased the drought in parts of south Texas last week. Two to five inches of rain fell south of Corpus Christi and Laredo which had been exceptionally dry. The drought is over in that area. The map to the right shows the drought conditions before Dolly. The areas in red indicate where rainfall is needed.

Houston, San Antonio and Austin need the rain too. But the rainfall was too light and too scattered in these areas to have an effect on the drought.

The heaviest rain from Dolly fell where the eye of the storm made landfall, of course. Over 12" of rain fell on the north side of the Rio Grande River Valley.  That area was already wet from rain earlier in the month.

Hurricane Dolly surprises some people. What?!!

Hurricane Dolly made landfall on South Padre Island Wednesday afternoon as a Category 2 hurricane with winds about 100 mph. The storm started off as a fickle tropical wave as many hurricanes do.  A few days later a strong storm was headed toward Texas.  The forecast track was spot on from the beginning. The intensity forecast called for a category one hurricane at landfall. But with every update, the National Hurricane Center stressed that additional strengthening was possible before the storm made landfall.

Yet, our reporters had no problems finding folks in Brownsville who said they were “surprised” by the storm.  One man told us, “I thought this was going to be a little tropical storm.”

Comments like that frustrate me.  At the beginning of every hurricane season we urge people to develop a hurricane plan for their family.  Even "little tropical storms" and category one hurricanes can produce significant damage and flooding.

A Hurricane Watch was issued for that area Monday morning at 11 AM.  By 10 PM Monday, that was upgraded to a Hurricane Warning.  No one should have been surprised to see moderate wind damage and heavy rain in that area. That's what a Hurricane Warning means.

Radar Xray looks inside Hurricane Dolly

A 3D slice of Hurricane Dolly clearly shows the slanted eyewall as the cyclone nears the Texas coast Wednesday morning.

Radar Xray is a weather analysis tool available exclusively in the Houston area on ABC13. This image was captured about 9 AM while the storm was still about 40miles east of Brownsville.

The first line of the grid represents 20,000 feet, then each additional line is another 10,000 feet. The precipitation with Dolly extended about 35,000 feet above the ground. That's lower than severe thunderstorms which can top out above 55,000 feet, but it's pretty typical for tropical weather systems.

The 3D cross-section also shows the bands of heavy rain east of the eye separated by dry slots. At the same time, rainfall in the eyewall is heavy over a wide area. Rain was falling at the rate of 4" per hour!

Hurricane Dolly strengthens as it nears land

The maximum sustained winds in Hurricane Dolly are a little stronger this morning. The National Hurricane Center reports winds are now up to 95 mph. Winds 96-110 mph are considered category two on the Saffir-Simpson hurricane intensity scale.

As of 9 AM, the eyewall was just starting to push into the barrier islands east of Brownsville. Landfall is noted when the center of the circulation crosses the coast, however. At 9 AM, the center of the eye was still 40 miles east of Brownsville. Official landfall will be just after noon and just north of Brownsville.

Closer to home, the outer rain bands have already dropped some heavy rain in our coastal communities, especially down near Matagorda Bay. Periods of rain will continue to spin across southeast Texas this afternoon. I'm still expecting about an inch of rain for Houston from these showers. Although heavier amounts are possible if the storms train one-after-the-other over the same spots.  Three to four inches is possible closer to the coast, again near Matagorda Bay. Lesser amounts of rain will fall north of I-10.

Track the showers on our MegaDoppler 13 radar.

You can also get the latest position and forecast track for Dolly on our website.

Dolly is now a hurricane

Data from Hurricane Hunters flying through Dolly this afternoon confirmed what we've been seeing on the satellite: this storm is now a hurricane with sustained winds at 75 mph. Some additional strengthening is possible before the storm makes landfall about 9 AM Wednesday morning.

For the latest position and forecast track, check our webpage.

It looks like the eye of the hurricane will make landfall just south of Brownsville, but the effects of the storm will be felt all along the coast.  The image to the right shows the wind field around the storm at 11 AM Wednesday morning. The yellow indicates tropical storm force winds. The orange indicates gale force winds of 50 mph. The extent of the hurricane force winds are noted in red.

The winds in the Houston-Galveston area will be a little stronger, but not powerful enough to cause damage.

We're just hoping for some rain! Scattered showers around the edge of the storm should get a few yards wet tonight. More showers will develop on Wednesday and Thursday as the moisture around Dolly moves across in. You'll be lucky if you get an inch of rain here.  4-6" of rain could fall in south Texas. Over 10" of rain could fall in the mountainous areas of northern Mexico.

Dolly could bring needed rain to south Texas

Tropical Storm Dolly might be a blessing in disguise. Several inches of rain could fall across the southern part of the state as the storm makes landfall. Over four inches of rain could fall from Houston to Corpus Christi. Even inland cities like San Antonio could benefit from this tropical cyclone.

Of course, the rainfall forecast will change as the track of Dolly changes. Amounts could go up or down if the storm slows down or speeds up. But the heaviest rainfall will probably fall along and to the right of where the eye makes landfall.

For the latest position and forecast track, check our webpage.

Most of south Texas is in the midst of a drought. Here's how far below normal some of our bigger cities are in terms of rainfall for the year:

• Houston -7.06"
• Galveston -9.65"
• San Antonio  -11.56"
• Victoria -9.46"
• Austin -7.69"
• Corpus Christi -3.77"

Droughts are often broken by tropical weather systems. The high winds we don't need. But a good, widespread soaking shower would be nice.

Tropical Storm Dolly probably not headed to Galveston

Although the official forecast cone stretches as far north as Galveston, Tropical Storm Dolly will probably stay south of the island. Our viewers around Matagorda Bay could be on the fringe of the system, however.

The computer models continue to show a track across the Yucatan and back into the Bay of Campeche. Dolly will probably make a second landfall in northern Mexico and/or south Texas.

Meantime, the National Hurricane Center has issued its last advisory on Bertha as it dissipates over the cold, north Atlantic. Tropical Storm Cristobal continues to move northeast off the North Carolina coast.

For the latest position and forecast track, check our webpage.