Monday, August 29, 2011

The Saffir-Simpson Wind Scale Is Exactly That, A Wind Scale

Now that Hurricane Irene has come and gone, many citizens up and down the eastern seaboard are left with power outages and widespread flooding. Most of the flooding is due to river flooding, where creeks, streams, and bayous will overflow their banks, creating a dangerous situation in which neighborhoods and communties could be devastated.

As I was watching this storm mature and move up the Atlantic seaboard, I kept on thinking of the similarities between Irene and Hurricane Ike, which came through East Texas nearly three years ago.

Both of these hurricanes were only category 2 hurricanes, according the the Saffir-Simpson Wind Scale, in which sustained winds were around 100-110 mph. However, both of them were unusually large hurricanes and had more widespread impacts than just the wind speed.

If you watched any of the national coverage over the weekend, you probably kept hearing meteorologists saying that the category does not do the storm justice for just how strong it is or the impacts it could create.

Unfortunately, public perception is that the category of the hurricane ultimately dictates whether or not citizens should evacuate or ride the storm out.

It should be noted that not all hurricanes are made the same and the category does not tell the whole story as to what the impacts could be.

Keep in mind that the Saffir-Simpson Wind Scale is exactly that, a wind scale. The category strength of a hurricane is only dependent upon sustained wind speeds and nothing else. It does not tell you about the size of the storm, the storm surge it could create, or the inland flooding that could result from the storm movement.

If you look at the 5 categories by which we classify hurricanes, you will also notice a range of pressure levels in addition to the wind speeds. It should be noted that the central pressure with Irene was around 950 mb. That would usually indicate a strong end category 3 hurricane if you look at the chart I attached. Instead of a category 3 hurricane, Irene was a category 2, with maximum sustained winds of around 110 mph.

Why the discrepancy? The storm was very broad and had an eye that was very large in diameter. We saw the same thing with Ike three years ago in which the wind speeds did not match up with the pressure of the storm.

Let this be a reminder that the next time we talk about hurricane strength, we are only referring to one aspect of the storm, that being the wind speed. That is why Hurricane Irene, which was mainly a category 1 hurricane as she moved parallel to the east coast, did way more damage and left a significant impact than most other category 1 storms.

Wednesday, August 24, 2011

Why The High Wind Gusts With Today's Storms?

Today's storms provided some beneficial rains to Deep East Texas, but it did come at a cost. That cost was damaging winds, which at times, were gusting over 50 mph.

These high winds occurred along a "gust front." A gust front is a boundary of rain cooled air that rushes out of a thunderstorm and then spreads out along the ground. They are often times associated with thunderstorm complexes, much like the one we saw today.

I was able to capture this radar image at 3:09pm this afternoon, when the gust front was encroaching on the Pineywoods. The gust front is the thin blue line that stretched from Center to near Mount Enterprise at this particular time.

It is that boundary which surged to the south and southwest preceding the rain that soon followed. Due to our drought situation, the high winds not only knocked down trees, but also kicked up a bunch of dirt, creating a scene you would typically see in West Texas.

Despite the fact the rain did not last as long as many of you would have liked, we did see a big drop in the temperatures once the storm complex moved through. Have you stepped outside this evening? The overcast skies and rain cooled air are something we have not seen in quite a long time.

For any updates on storm damage or to see all the pictures sent in from our loyal viewers, make sure to view our homepage at

Monday, August 22, 2011

Hurricane Irene Brings Both Good and Bad News

Hurricane Irene continues to strengthen as she churns through the western Atlantic Ocean. She has already done damage to Puerto Rico and is currently spinning just to the north of Hispaniola.

The strength of Irene will highly depend on whether or not the center of circulation can stay away from Haiti and the Dominican Republic. If the center stays out over open waters, which most models agree on, then Irene will strengthen even further, possibly into a category 2 hurricane by tomorrow.

Irene will continue to track off to the northwest and is slated to make landfall somewhere along the eastern seaboard this weekend, possibly as a major hurricane. While the center of the track brings landfall into the Carolina's, there is still a lot of uncertainty in regards to where exactly she will end up since we are still five days away.

The average forecast error this far out (5 days)averages around 200 miles. That's why areas such as the east coast of Florida to the Virginia's are in the cone of uncertainty.

The track of Hurricane Irene will be bittersweet for us. The good news is that we won't have to deal with a hurricane. However, we could use a tropical depression or storm to help alleviate the ongoing drought.

There are a few more tropical waves well out in the Atlantic Ocean, but at this point, they don't appear to be threatening the Gulf of Mexico anytime soon.

Remember that you can stay up-to-date with the current position, forecast track, intensity forecast, and links to the National Hurricane Center by going to our Hurricane Center on It even shows you the latest radar and satellite images.

Tuesday, August 16, 2011

These Records Aren't Something To Be Proud Of

As I mentioned on air the other day, breaking records and obtaining them are typically a good thing in life, except when it comes to weather. When dealing with weather records, we are talking about extremes in some shape or form.

For instance, record cold, record heat, record rainfall, record drought, etc. are the kinds of things you don't want to hear or see reported in your local weathercasts. Unfortunately, weather records don't go hand in hand with records obtained in sports or any other endeavour for that matter.

As of this evening, the Angelina County Airport in Lufkin has had 42 100° days this year. That ties the mark for the most number of 100° days that last occurred in the hot summer of 1998. We will break that record tomorrow and then shatter it as we progress through the second half of August.

On average, we see about 2 days of 100° temperatures heading into August, and about 7 days of triple digit heat per year. We have exceeded the average mark by a factor of 6 and still climbing.

More Heat Records

Not only are the number of days over the century mark a talking point, but so is our current streak of consecutive 100° days. We are at 18 days in a row, in which the temperature has hit or exceeded the century mark. That too, is an all time record for consecutive days being in triple digit territory. This treak started back on July 30th and has continued ever since.

No Relief in Sight

Outside of a stray evening shower or storm, there is no real relief to speak of. It looks as if our triple digit heat will continue right through the weekend and into next week.

Thursday, August 11, 2011

Signs That Fall Is Near

It seems like we are beating a dead horse, but the heat has been a big topic so far this summer, due in large part to record highs and the number of triple digit days. While it seems like there may be no end in sight, there are some positives to point out as we head through the rest of August.

It should be noted that we are just a little over a month away from the start of fall. Each day is getting a little shorter in length (sunrise occuring later, sunset earlier) and the sun angle gets a tad lower in the sky as well.

Another sign that fall is just around the corner is when we start talking about "cold fronts." Yes, I did say cold front.

We have had a cold front trigger storms the past few days in Oklahoma, Arkansas, and North Texas.

Our Futurecast computer model shows another cold front that is slated to move into East Texas over the weekend. While there is still some discrepancies on how far south the front will advance, we could see some slight rain chances return to the forecast due to its presence alone.

I should caution you that this front will not bring us any relief from the heat. However, it could increase the clouds and give way to a few showers and storms to help out a few of us by the time we head towards Sunday and Monday of next week.

Monday, August 8, 2011

The Heat Keeps Coming and Coming

The unrelenting August heat continues to hold its grip over Deep East Texas, due in large part to a big dome of hot, high pressure, centered right over the Southern Plain states.

This high pressure ridge started to expand and strengthen in June and has been stuck in neutral for most of the summer months. As a result, we have seen day after day of record heat and scorching temperatures across the Lone Star State.

A July Fry to Forget

This past July was the second warmest July on record at the Angelina County Airport, just south of Lufkin. The average temperature for that month was 86.9°, which was 4.3° above normal. The warmest average July on record took place in 1998, where the average temperature was 87.7°.

July was also historic in the number of 100° days we saw as well. The 16 occurrences was second all time, only to the July of 1998, where we saw the thermometer climb at or above the century mark 22 times that year. To put the frequency of triple digit days in perspective, we typically average about 3 triple digit days for the entire month of July.

Triple Digit Days Adding Up

As of today, we have now hit or exceeded the century mark 34 times in 2011. The highest frequency of 100° days in a single year was 42, which occurred in the hot summer of 1998. At the pace we are on right now, we will more than likely break that record.

The Drought a Major Player

The overriding factor for our sizzling summer temperatures has been the ongoing extreme to exceptional drought across the Texas Forest Country. With the soils being parched and extremely dry, there is no moisture to evaporate into the atmosphere. Therefore, it makes it a whole lot easier for the environment to heat up, especially when we get into the months of July and August.

Not as Oppressive, But Not Much Relief

As we head through the week, daytime highs are still expected to reach triple digit territory with relative ease. However, the dome of high pressure will not be as strong as last week and will be shifted slightly furthur to the west. This means that we will take an edge off the extreme heat and will see slight rain chances re-enter the picture.

Monday, August 1, 2011

Summer Heat Elevated to Dangerous Levels

We are entering the month of August with the hottest weather we have seen so far this year. While feeling the triple digit heat is not all that uncommon in August, what is unusual is how high the mercury will be climbing each afternoon this week.

On Monday, we reached 106° at the Angelina County Airport, just south of Lufkin. That reading was the hottest day we have seen to date so far in 2011. Unfortunately, it could get worse in the days ahead, as a big dome of high pressure strengthens and situates itself over the Southern Plain states.

This is the type of weather pattern which often gives us a stretch of triple digit temperatures this time of year. However, just as we've seen through the spring and summer months so far, this summer is not your typical summer. It has been unseasonably hot, due in large part to the exceptional drought, which continues to plague most of the state.

With that dry ground in place, it makes it easier for the temperatures to heat up, especially now that we are in the month of August.

With our hottest stretch of weather setting in this week, the National Weather Service has put several of our East Texas counties under an "Excessive Heat Warning." This is a step up from the regular heat advisory that we typically see issued this time of year.

What this advisory means is that heat stroke and/or heat exhaustion can set in very quickly, especially if you find yourself outdoors for an extended period of time.

While advice on how to keep cool is common sense, there is one thing I want to point out that I feel is vitally important to those of you that don't have air conditioning: Please seek that A/C if you don't have any. This might mean calling a friend or neighbor, and having them take you in at their place of residence. Another option would be to go to a mall, movie theater, grocery store, or restaurant that has air conditioning. Try to take advantage of these public facilities that have air conditioning.

It is during these types of heat waves we often hear about heat related deaths and illnesses. Please don't let yourself or a close friend be a victim. Let's take care of ourselves and each other and make sure we are doing what is necessary to stay cool during this heat wave.