Thursday, May 27, 2010

Looking Towards Memorial Day

Well some much needed rain hit arts of East Texas yesterday but will this rain ruin your Holiday Weekend plans? Today we will see hot and humid conditions again today but, not quite as humid as yesterday. This will keep the overall coverage of thunderstorms less from what we saw yesterday. A few places could receive some much needed rain but it looks like the chances of rain where you live today are less than 20 percent. Any storm that forms today could produce small hail and strong gusty winds although we are not anticipating much in the way of severe weather.

Tomorrow a ridge of high pressure in the upper levels of the atmosphere will begin to build back into East Texas. This will cause the air to sink across most of the area eliminating the threat of afternoon storms. The one exception to this will be across our far southern counties where from Crockett to Lufkin to Hemphill we could see an isolated storm tomorrow afternoon.

This ridge will of high pressure will stick around through Sunday keeping most of East Texas dry and warm. Some slightly drier air will mix down during the afternoon hours so the heat index will not be quite as hot as we have seen this week. This should also allow for nighttime temperatures to dip down into the middle to upper 60s.

As we head towards Memorial Day, it looks as though most of East Texas will continue to remain dry. The ridge of high pressure will begin to break down just a bit so we can’t rule out a pop up storm developing but I wouldn’t cancel those outdoor barbeques just yet. You can always see the weather where you live by clicking out interactive radar to help you with your outdoor plans.

Stay safe and everyone have a great Memorial Day Holiday, and remember why we celebrate.

Wednesday, May 26, 2010

May 20th 2010 Storm Chase

Well it has taken me awhile but I am finally writing my chase account from last Thursday May 20th. The severe weather set up from Thursday event included an outflow boundary interacting with a stationary front across Central Texas just south of Dallas.
Early in the afternoon strong to severe storms developed along and north of a southward moving outflow boundary from Wednesday’s convection farther north. These storms became severe and produced wind damage in the Dikes community of Hopkins County, just east of Sulphur Springs.

It was along the intersection of the southwestward moving outflow boundary and stationary front where supercells would continue to develop throughout the afternoon and move off to the south and east. There were two official tornado reports and numerous reports of large hail, up to baseball

The first storm we encountered was in Henderson County near the Cedar Creek Reservoir. This storm was showing signs of weak rotation but no true wall cloud feature was seen while we were on the shores of Cedar Creek Reservoir. As we drove south from Tool along 247, we noticed an elephant trunk shaped funnel extending towards the ground. From our vantage point we could not tell if this funnel reached the ground or not. By the time I could snap a shot of the funnel, it was much farther off the surface and more horizontal. This storm continued to produce these funnels that would not quite reach the ground. It looked as though as these funnels lowered, the cooler air from behind the outflow boundary was undercutting the updraft causing them to rope out before even reaching the ground. This storm produced at least three funnels before moving away from our vantage point.

From this storm we raced west to catch the latest storm that had developed along the intersecting boundaries. This storm was showing signs of strong rotation both on radar and from our ground view. Although this storm would not go on to produce a tornado, large hail did occur. We were hit with quarter size hail wrapping along the back side of this storm..

Our third storm became the storm of the day for us developing near Waxahachie and moved southeast through Navarro and Freestone Counties. This storm would go on to produce wind damage and hail up to the size of Baseballs near Corsicana. From our vantage point it also appears that a brief but rather wide tornado could have touched down over Richland Chambers Lake.

As we approached this storm radar showed a very well developed deep convective supercell, a constant midlevel rotation was show on this storm for well over an hour.
As this storm moved over, we raced south to stay out of the hail core. For a time we were under a large rotating wall cloud. It was during this time that I witnessed an event I have never seen before. We noticed mini vortices about 5 feet in diameter rotating around the wall cloud. Three or four of these little vortices moved in front of our vehicle. The did not appear to be in contact with the storms updraft but it was interesting that these dust devil size vortices were moving in the direction of the parent circulation. Were these mini vortices a precursor to a developing tornado? I am not sure but it was an event I had never witnessed before.

We finally moved out ahead of the wall cloud and drove down I-45 to Streetman. It was here we noticed a circulation that appeared to be in contact with the cloud base, a brown swirl rotating around a large bell funnel. I quickly grabbed my camera and took a photo.
The contrast on the storm was very poor so it was hard to exactly see what we were seeing. By taking the photo and zooming in a bit and adjusting the contrast, you can see a funnel with what appears to be debris rotating around. Here the debris, which at first was brown is now white. It is at this time when the funnel moved over Richland Chambers Lake and the white debris appears to be water. The next image is a radar grab from the storm two minutes before a snapped the shot of the funnel. There was strong rotation but not a tight as what you would like to see for a strong tornado. This could be why there was very little damage on land before this feature moved over the lake. We drove looking for a damage path but could only find sporadic snapped trees along with one weak structure with its roof blown off. Was this a large EF-0 tornado? We will probably never know. Officially this will go down as a severe thunderstorm with baseball size hail and sporadic wind damage. But form our vantage point; it looks as though a tornado could have occurred as well. Next time I will roll video instead of taking a snap shot. Then everyone could see the rotating funnel and debris wrapping around that we saw.

Thursday, May 20, 2010

Chances of severe weather increase this afternoon

Yesterday’s conditional severe weather threat turned out to be nothing more than a few clouds thanks to the warm front moving farther into Oklahoma. Storms that erupted on this front rapidly became severe producing many tornadoes and large hail to our north.
Today most of East Texas is under a slight risk of severe thunderstorms this afternoon. After looking over this morning data, it appears much of East Texas is under the risk for large hail, possibly up to golfball size and strong gusty winds. A very unstable atmosphere is in place across East Texas with a weak cap, or layer of warm air just of the surface. As we warm up this afternoon the cap will weaken allowing for thunderstorms to develop. Storms will be scattered in nature so everyone will not see them but any storm that develops could become severe. We are also noticing an outflow boundary from yesterday’s storms between the I-20 and I-30 corridor. We will have to watch this boundary very closely because if any severe storm were to attach itself to this boundary, low level rotation could increase and we could see an isolated tornado or two if this occurs. The greatest risk of severe weather across East Texas is along and south of an Emory to Quitman to Jefferson line and north of a Crockett to Lufkin to Hemphill line.
Storms should begin to move out of East Texas late tonight into the pre-dawn hours tomorrow. This will set the stage for a very warm and humid weekend. Highs will reach the lower 90s in most areas but could approach the middle 90s from Crockett to Lufkin to Hemphill. In these same areas the Heat Index could approach 100 degrees.

Friday, May 14, 2010

It’s taking a while but, much needed rain is on the way

The cold front we have been advertising for days has stalled out to our west this morning. We are still anticipating this front to move into the area overnight tonight increasing the chance of rain for all of East Texas. This afternoon we will see a few scattered showers and storms develop thanks to day time temperatures reaching the middle to upper 80s. These storms will be few and far between so unfortunately, most areas will remain dry.

It is tonight that our front will begin to sag south into East Texas and with it, our rain chances increase. It looks as though we will see off and on thunderstorms throughout the weekend so keep the rain gear handy. As you can see from the forecast rainfall across the area, most of East Texas is forecast to have at least 1.5” of rain, the purple colors on the map.

A disturbance will move through the area Sunday night and push the cold front off to our east. There is a chance that as this disturbance moves through Sunday night, very heavy rain could occur. A few of our forecast guidance suggest some areas could see over 3” of rain. We will have to monitor this very closely. Due to the lack of rain, heavy rain will run off increasing the threat for flash flooding. Again this is not set in stone and a lot could change between now and then. Stay with your East Texas News Leader for the latest.

Thursday, May 13, 2010

Much Needed Rain On The Way

Over the past few weeks much of East Texas has fallen further behind in average rainfall with much of the area now 6 to 8 inches below normal. This rainfall deficit has dried out the soil from fall and winter rains to produce dry vegetation. This also has been allowing for our temperatures to be well above normal the past few days with highs reaching the lower to middle 90s across East Texas.

Well all this is about to change this weekend. Now we are not expecting to knock out the rainfall deficit but in a few areas, a major dent in the deficit will occur. This morning we are tracking a cold front out to our west. Strong thunderstorms producing very heavy rain and hail are developing to our west late this morning and will be heading towards our area later today.

Now for most of East Texas today looks dry. We will see a few isolated storms develop during the peak daytime heating hours, especially over our western counties. The cold front will move into and stall out across our area during the day Friday. As this happens, showers and storms will develop. The heaviest concentration of rain will be north of I-20 where the greatest amount of moisture and lift will be available. But areas across our southern counties could even see a few thunderstorms develop Friday afternoon thanks to greater daytime heating and instability.

Overall it looks as though areas north of I-20 could receive 1 to 2 inches of rain this weekend with greatest amounts near the Sulphur Springs and Mt. Pleasant areas. As the front continues to sag south, a greater chance of thunderstorms will occur across the Nacogdoches Lufkin and Hemphill areas on Saturday producing up to or slightly over 1 inch of rain. So we will not make up our rainfall deficit this weekend but take a big step towards getting closer to normal.

As for the threat of severe weather with this system, the overall threat looks fairly weak. There is a slight chance one or two storms could become marginally severe producing hail and gusty winds but the atmosphere right now appears it will not be conducive for severe storm development.

Friday, May 7, 2010

A Severe Storm Possible Today

Another warm humid day is in store for East Texas this Friday with temperatures once again approaching the 90 degree mark. However, today we have a cold front moving into the area and this front has the chance to produce a couple of storms later today. The storms that do develop along this front will only be isolated but could pack quite a punch. Right now it appears a few storms could produce large hail around the size of quarters and gusty winds up to 60 mph. Due to the isolated nature of these storms, the Storm Prediction Center has removed most of East Texas from the slight risk of severe weather today. But we will continue to monitor this developing situation. The greatest chance of seeing a severe storm this afternoon would be from a Center Alto Crockett line and points south.

After the cold front moves through this evening, a very pleasant day is on tap for our Saturday. We will see a few clouds however; northeast winds will bring very dry air into the area. Afternoon temperatures in the middle to upper 70s will make for a very pleasant afternoon.

It still looks as though the front will move back to the north on Mother’s Day. We are not anticipating wide spread rain or storms with this warm front but a few areas could see rain. Right now it appears the Lufkin Nacogdoches areas could see scattered showers during the morning hours with the activity moving north throughout the day. Scattered showers will be possible along I-20 by midday and by I-30 during the afternoon hours. Again, this does not appear to be a wide spread rain event and most areas will remain dry. To keep up with the latest throughout the weekend be sure to check out our interactive radar to see if it will rain where you live.

Happy Mother’s Day to all the Moms out there!