KATC StormTeam 3 Weather BLOG

We had much welcomed rain today with another round of scattered storms expected Friday. I don’t expect any severe weather but at least the rain will cool us off for a while in the afternoon. This rain is caused by a mid level trough and as it moves east and high pressure moves in, our rain chances will go down Saturday. By Sunday we will have  nothing but sunny skies and temperatures will heat up to the upper 90s. Some of that dry air  from aloft may make it down to the surface which means lower humidity, keeping the heat index in check. If dew points are allowed to reach into the 70s then the heat index could reach as high as 109 Sunday and Monday.

To break the heat wave an upper level low in the Gulf will sling some moisture our way on Tuesday increasing our rain chances. We will keep a chance of rain each day through the end of the week as our atmosphere stays humid. The tropics are looking good with just a couple of tropical waves but nothing expected to develop. One wave off of the African coast is over some relatively cool water and has fizzled out. The other is near Puerto Rico but upper level winds are not favorable for that to turn into anything much stronger.

As expected the weak disturbance just off the Louisiana Coast has hurled some tropical moisture into Acadiana bringing clouds with scattered thunderstorms across the area. Tomorrow should bring better coverage of the storms with chances of getting wet increasing to at least 50%. We do need the rain and also the break from the heat should be nice with Wednesday’s projected highs near 90. The disturbance in the Gulf looks small but impressive on the visible satellite imagery with some mid-level cyclonic turning showing. Buoy, ship and platform data have not shown organized winds nor have pressures dropped; however, this feature is under a tropical ridge aloft. Therefore, some weak development could be possible as long as this feature remains over water. This disturbance is expected to drift inland across the area late tomorrow and then weaken and get sheared off to the northeast as a very weak frontal trough drops down from the north later this week. The bottom line should translate to a good chance of showers and storms tomorrow with a better than average chance of showers and a few storms through the end of the week. It will get a little hotter this weekend with highs pushing back into the low-mid 90s but there will still be the chance of a few afternoon storms. The longer range models are interestingly enough indicating another disturbance that may spin off from the aforementioned frontal trough over the Gulf States this weekend and then drift westward across the area next week so we could see enhanced rain chances again by Sunday or early next week. Elsewhere in the tropics a couple good looking waves have emerged off the African Coast.

After three days in a row with temperatures in the upper 90s we are somewhat optimistic on a few more clouds with a few showers and storms to help reduce the heat (a little) tomorrow through Thursday. A weak disturbance in the form of a surface trough and weak upper low off of the southeast coast of Louisiana will drift westward through Wednesday, allowing for deeper tropical moisture to move into at least parts of Acadiana, especially coastal and eastern parts through mid-week. Therefore we should see more clouds, earlier in the day limited the hot temperatures to the mid-90s, but as winds turn more SW’rly tomorrow afternoon our humidity will increase slightly thereby keeping heat indices close to the 105 degree mark during the afternoon. Rain chance tomorrow should increase to 20-30% and will be in the neighborhood of 40% for Wednesday and possibly Thursday. Highs will hopefully drop into the lower 90s for Wednesday and Thursday but unfortunately the ridge of high pressure will re-strengthen by the weekend, knocking the rain chances back down to the low side while highs creep back into the mid-90s. The tropics remain rather quiet other than the aforementioned weak trough in the Gulf of Mexico. At this point we are not expecting any development with this feature but if it persists for more than a day or two that could change.

It’s going to be a very hot weekend as high pressure expands with highs reaching the mid-upper 90s across much of Acadiana. Heat indices will likely reach the 105-108 degree mark which put us in the “danger” zone on the heat index chart. So stay hydrated and try to limit your time in the heat, and make sure you check on the elderly. Excessive heat is one of the biggest “silent” weather killers in the U.S. and we don’t want to add to the statistics over the next few days. Rain chances should stay near 20% or less through at least Monday, but there are signs that the ridge will weaken enough to allow for more in the way of scattered storms mid-late next week. After a busy period in the tropics, activity has quieted down nicely with just a few tropical waves in the open Atlantic. A moderate wave located near 23N and about 43W may develop down the road, but this system should stay an Atlantic system.

Hurricane Dolly maxed out this morning as a Category 2 storm prior to landfall. Now Dolly’s winds are decreasing but the rain hasn’t been going anywhere, with serious flooding rains likely across much of South Texas through tomorrow. Fortunately Acadiana benefited from tropical moisture with most areas receiving between .10” and .50” with a few spots across the coastal parishes catching several inches. Many spots across Cameron Parish saw 2-3 inches today. An added plus was the additional cloud cover that kept our temperatures in the 80s this afternoon. Lingering tropical showers will diminish later this evening with rain chances down to the slight category overnight. Tomorrow will bring a little more sunshine with scattered mainly afternoon showers and some locally heavy thunderstorms possible. Temperatures should return back into the lower 90s Thursday but should be back into the mid-90s Friday and the weekend as high pressure redevelops across the region. So expect big heat with just a slight chance of an afternoon shower or thunderstorm this weekend into early next week. Hope you enjoyed the break!

The National Hurricane Center upgraded Dolly to hurricane status this afternoon as the system continued to churn toward the Lower Texas Coast and Northern Mexico. Fortunately for us, the only effects from Dolly will be another day with plenty of cloud cover accompanied by a better chance of getting wet by tropical showers and thundershowers and elevated tides along the coast. Some gusty winds and heavy downpours can be expected as Dolly makes landfall Wednesday with tropical moisture spreading radially from the center of circulation. Typically at night, tropical rain bands concentrate near the center of a tropical system, but during the day, and especially when a system makes landfall, wind and moisture fields expand. Combining that factor with daytime heating should produce a healthy round of tropical showers across Acadiana. A few funnel clouds would not be surprising in a few isolated cells so we’ll be watching the radar closely tomorrow. A Coastal Flood Watch remains in effect as tides rise from 1-2ft above normal this evening to 2-3ft above normal Wednesday. Tides could reach 4ft above normal along the Cameron Coast with water possible reaching Highway 82 near Holly Beach. The more quickly Dolly makes landfall, the lower the tides will be. Tides along with the rain chances will decrease Thursday. But we could see enhanced rain chances and some quite healthy storms late Thursday as a frontal trough over the SE U.S. could send an impulse to the southwest that could interact with the residual tropical moisture in our area. More typical summer weather with scattered afternoon showers and storms are expected Friday through the weekend.

Check this latest Google Earth tool that tracks Hurricane Hunter Data! Ed Roy called tonight to let me know about this just released mash-up to track the data coming in from the Hurricane Hunters. The investigating plane shows detailed observation every 30 seconds, including dropsonde data and complete decoded vortex messages. Enjoy! Have to get ready for the 10pm show…Rob

It will be all about “Dolly” over the next 24-36 hours as this system is heading for the warmest waters (85-88 degrees) in the Gulf of Mexico later tonight and tomorrow. The major impacts with this system should bypass us to the south but we will likely see some fringe effects across Acadiana, especially across the coastal parishes. Dolly is expected to continue on a west-northwestward path but slow down tomorrow over the warmest part of the Gulf. Therefore, Dolly has good potential to become a hurricane prior to a Wednesday landfall across the Lower Texas Coast, with the National Hurricane Center indicating at least Category 1 potential. Fortunately a ridge of high pressure aloft over the Northern Gulf Rim should stay strong enough to keep Dolly on the projected path but there will likely be some sort of an enhancement to our rain chances for late tomorrow and especially Wednesday. In addition, swells will build in along our coast from the south and east later tonight with tides likely increasing to 1-2ft above normal tomorrow and possibly 2-4ft above normal on Wednesday. Check with the National Weather Service regularly for the latest updates and also download the KATC Desktop Weather Lab so you have the latest watches and warning data available locally instantly on your desktop. Right now just a Coastal Flood Advisory is in effect for Cameron, Vermilion, Iberia and St Mary Parishes, but additional coastal watches or warnings will be possible along the coast through at least Wednesday. Our rain chances inland could be enhanced tomorrow and should be Wednesday possibly into Thursday but forecasting where tropical rain bands form is always tricky with well–developed tropical systems producing sinking air around them cutting down on activity…they can also enhance activity depending on how perturbations from the storm propagate away from the system, and what phase the storm is in. Our most prudent course will be to raise the chance of rain through mid-week with the pattern settling down to a more sedate summer pattern later this week. Stay with KATC for regular updates…Rob Perillo

It’s an active weekend for tropical activity as Tropical Storm Cristobal developed off of the Carolina coasts and Dolly strengthened over the Northwestern Caribbean. Cristobal is expected to move up the Atlantic coast over the next few days and increase in foward speed as it weakens. 

Dolly is headed for the Yucatan Peninsula as it continues on a northwestward track. The storm is expected to emerge over the southern Gulf and strengthen. Computer models at this time mostly agree on a track into Northern Mexico or Brownsville, TX on Wednesday night into Thursday. We need for the high pressure over us now to keep its intensity and Dolly will stay well to the south of here.

The last advisory has been issued on Bertha which is in the far north Atlantic and has become extratropical. Bertha has gone down in the record books as the longest lived storm in the Atlantic basin for the month of July.

As for our weather, expect one more sunny day on Monday before the rain chances return. Tuesday and Wednesday will hold a good chance of rain as moisture surges in out of the Gulf. That will provide a juicy atmosphere for daytime heating and seabreeze storms. But that moisture will be shut down toward the end of the week giving us lower rain chances.

A typical July weekend is forecast with hazy, hot and humid conditions likely along with just a few afternoon storms through Monday. The tropics remain busy with Bertha back to hurricane status, a disturbance of the SE U.S. Coast and a vigorous tropical disturbance in the Caribbean. Hurricane Hunters once again failed to find a closed circulation typical of a tropical depression with the system near Jamaica but it still looks like we’ll see a change in the pattern as this impulse traverses the Yucatan this weekend and heads for the Southern Gulf early next week. Whether this system develops or not I would expect a healthy surge of tropical moisture to add to our rain chances mid-next week. This system could still become a depression this weekend before crossing the Yucatan and if not possibly in the Southwestern Gulf so we’ll remain vigilant. The hurricane/tropical models are less aggressive than they were yesterday with this system while the broader global models take the entire impulse into Texas or Mexico by next Wednesday/Thursday. In the near term this evening, the International Space Station should be visible this evening at 8:44pm in the south-southwestern sky heading to the east-northeast about 29 degrees above the horizon. Haze and some high clouds may limit our viewing tonight but if your check the link we’ll have a few pre-dawn and evening views possible. Have a great weekend.