MTW Discussion

Hot and dry weather continues to plague South-Central Texas as a powerful subtropical ridge tightens its grip across the Central US.  Expect high temperatures to hover at or above 100 throughout the next several days with limited to no chance for rain.  The exception would be Saturday through Tuesday when the ridge’s influence slightly weakens allowing for isolated sea breeze showers to develop generally south and east of San Antonio.

There are also two tropical systems we are monitoring: One located to southeast; the other is Hurricane Andres in the Pacific.   Neither system will affect our forecast.

The aquifer level is still dropping at a fast rate.  Stage 3 water restrictions will be possible by next week.

First, let’s begin with some good news.  For the first time in quite a few days, the San Antonio International Airport stopped short of reaching the century-mark for the high.  Instead, our high was a balmy and lovely winter-like (well maybe only in South Texas) 99ºF.

Now back to reality:  this streak of hot and dry weather does not look like it is going to end anytime in the foreseeable future.  The culprit?  A powerful and incredibly stubborn ridge of high pressure that will not go away.  Storm systems keep riding around the high to our north and to our south.  But, unfortunately for our friends up north, many of the systems are providing plenty of severe weather.  Large hail, damaging winds, and tornadoes have been occuring nearly daily in the upper midwest, and today will not be an exception.  More storms are expected to fire up in the upper midwest and head towards the Ohio Valley. However, again for us, we will remain hot and dry.  Did I say that already?

The problem is… we need rain BADLY.  The Edwards Aquifer is dropping at a rapid rate.  Here is information regarding the Aquifer elevation at the J-17 Well here in Bexar County obtained from the Edwards Aquifer Authority since Saturday when we entered Stage 2 Water Restrictions Criteria:

June 13 - 649.6′
June 14 - 648.2′
June 15 - 648.7′
June 16 - 647.2′
June 17 - 646.0

and right now at 4:00 AM, the aquifer stands at 644.91′ where it’s been sitting since 1:45 AM.

The trigger for Stage 3 Water Restrictions is 640 feet above sea level.  At this rate, we’ll be there in a matter of a few days.  The water rules then are much stricter, and you can find out more about them at the SAWS webpage linked on MyTexasWeather.com.  The biggest change once Stage 3 is implemented will be the fact that you can only water with a sprinkler once every other week, instead of weekly.

It is imperative that we as a community conserve our water, it’s a precious resource.  And in droughts like these, you cannot save enough.

Looking in the long-range, I’m not overly optimistic, but I am seeing some possible changes.  One of the models wants to push the ridge further north, which will help bring us in the path of the easterly trade winds.  Under such scenarios, any disturbance in the Gulf will be pushed up in our direction bringing us nice and healthy tropical downpours.  Right now the model indicates any such chance for storms around the first week of July… which is still quite a ways away.   But, at this rate, mentioning anything is a good thing and something we can keep our fingers crossed to see verify.

Other than that, keep cool and conserve as much water as possible to slow the drop of the aquifer.

Expect more of the same weather to continue throughout the next several days across South-Central Texas. We remain under the influence of an extremely powerful subtropical ridge of high pressure. This will suppress any chances for relief in the form of rain or cooler temperatures. A persistent south/southeasterly wind at the surface will usher in enough moisture to keep humidity levels up, yielding nasty heat index values of near 110º throughout most of the week. There are no signs of this mid-late summer pattern to break down any time in the foreseeable future.

Unfortunately the Aquifer continues to be taking continuous hits from this latest dry and hot spell.  Yesterday’s reading was 647.2 ft at the J-17 well in Bexar County.  Today is shaping up to hang around 645 or 646 based on latest trends I’ve been monitoring all night.  The trigger for rigorous Stage 3 watering restrictions is at 640 ft.  We may approach that critical level by next week if the trend holds.  CONSERVE WATER!

Our 8-day forecast is calling for 100º+ temperatures everyday.  Exercise caution when performing outdoor activities and avoid strenuous workouts during peak heating hours. Also remember to keep hydrated at all times.

Usually the song and dance for forecasting the weather in South-Central Texas is never underestimate the power of the ridge.  That is what usually keeps us dry and the reason why we miss out on so many storm events.  Last night, that was not the case.  We underestimated the power of a nice shortwave trough in West Texas that pushed eastward firing up a very steady and heavy batch of showers and thunderstorms that roared all night long into the early morning hours.  Some of these storms did in fact reach severe limits.  There were reports of a funnel cloud near Leakey, pea sized hail in Hondo, and a gust to 58 mph.  Here in Bexar County we saw some very heavy rainfall, gusty winds, and an awesome display of lightning. I originally expected that these storms would fire up by Tuesday evening/overnight … instead, we were all surprised by their early arrival.

What does this mean for today’s forecast?  It is actually a no-brainer — more of the same.  This morning’s Doppler radar and infrared satellite imagery continue to indicate several impulses activating in West Texas and Northern Mexico pushing eastward into the region.  The next line of storms has already developed and should cross the border into western portions of South-Central Texas fairly shortly.  These storms will probably make it to the San Antonio-Metropolitan area/ IH-35 corridor around lunch time. Again with these storms the main threats will be heavy rainfall, strong winds, and large hail.  An isolated tornado cannot be ruled out.  I do not expect a widespread outbeak of severe storms due to the lack of upper-level dynamics, but there is certainly more than enough instability to get these storms going strong.  And behind this?  Another round of storms will move through the region yet again later this evening into the overnight hours.

Thunderstorms remain again in the forecast on Thursday and Friday, albiet less organized than last night and today.  Most of the storms will be the product of daytime heating and will fizzle out after sunset.  A late season cold front may move through by Friday ending our rain chances at least temporarily.

Another series of disturbances is forecast to approach South-Central Texas by Sunday and continue through at least the early portions of next week. As a result of all the precipitation, high temperatures should be much more moderate than previously anticipated.  We will not see nearly as much sunshine so I have reduced highs to hover between the mid 80s and low 90s the next 8 days.  Overnight lows will be in the mid 60s to about 70 accounting for the possibility of rain-cooled air.

Quite an amazing shift in our weather pattern considering how long and brutal our drought, which began in September 2007, has been.  And as always, we will surely keep a very close eye on each and every storm system that moves through the region.

Should inclimate weather affect our region, we will do our best to notify you immediately.  Check our Twitter, frontpag e, and Live Streams on MyTexasWeather.com for the latest updates.

Stay tuned.

There were several areas that saw showers and storms this weekend across South-Central Texas.  Rainfall totals range from nothing to several inches.  However, the ones who were short-changed are few and far between.  Some of the storms did reach severe limits.  Lackland AFB around 2:30 PM on Saturday measured a wind gust of 72 MPH and small hail was reported across parts of Northern Bexar County Sunday afternoon.

Luckily, the storms have moved out just in time for Memorial Day across the region.  Most of the storms will remain across East Texas and the northern Gulf Coast states.  This means that we will enjoy excellent barbecue/pincic weather here in South-Central Texas.  That is, if you can handle the heat and humidity.  Highs should top out in the low to mid 90s today under generally clear skies, with a few clouds here and there. Pack the cold beverages if you are going to stay outside.

Tomorrow will be another warm day, but not looking nearly as warm as previously anticipated.  If you remember in earlier discussions, the mitigating factor to how hot it would get was how much rain we saw this weekend.  And since many locations recieved healthy rainfall totals, I think that the moisture in the soil and vegetation will help inhibit high temperatures and keep most areas in the eastern 2/3 of South-Central Texas below the century mark.

By Tuesday Night, another disturbance will enter the area bringing the chance for more showers and thudnerstorms.  The probability for more storms will be on the increase Wednesday and Thursday as a front approaches the region.  In fact, some models are bringing the late-season front through here by Friday or Saturday.  This should buy us a couple of dry days as models bring in yet another system by early next week.

Happy Memorial Day and we solute the soldiers who make this country what it is.

Stay tuned.

The 2009 Atlantic Hurricane Season does not begin for another few days, but there is plenty to watch in the Gulf of Mexico right now. Just east of New Orleans there is a very well organized tropical disturbance packing tropical storm force winds to the northern Gulf coast. The National Hurricane Center rates the probabilities of tropical cyclone formation as high. The mitigating factor inhibiting development prior to landfall is the proximity to land. As of 1:30AM CDT, the center of circulation is approximately 50 miles from land. With the storm moving essentially due north, it may not have enough time over water to fully develop a closed circulation and reach Tropical Storm status. However, if the circulation does close, I suspect the National Hurricane Center will name the storm Ana immediately as maximum sustained winds are well over Tropical Storm force.

Should “Ana” be declared, MyTexasWeather will keep you updated. Check out our Tropics page for the latest information.  I don’t think that this storm will have much of an effect here on South-Central Texas as the upper level jet should push most of the energy out east.

Meanwhile back out here, we are tracking a weakening ridge and numerous storms that develop with the help of daytime heating.   The capping inversion I briefly discussed last time eroded much quicker than anticipated, which is why many of you reported rain yesterday and why we say so much lightning overnight.  The same general setup should persist through the weekend with scattered hit and miss thunderstorms.  I do think these storms will be slightly more numerous this weekend than they were Friday.  Due to the lack of upper level winds, these storms will move very slowly if at all.  However, the good news is that the lack of sufficient wind shear will prevent these storms from reaching severe limits. But, I would not be surprised if a couple of these storms get strong enough to drop small hail here and there.

By Monday and Tuesday the winds will shift to the South and Southwest.  This will help reduce the humidity but also increase the temperatures drastically. You may want to limit the amount of heat you add to the barbecues on Memorial Day as the outdoor air temperature should suffice.  Highs on Monday should hover in the mid 90s under partly cloudy skies.  Tuesday, however, may top out near 100 degrees.

Beyond Tuesday, a series of shortwave troughs will move through the region allowing for storms to develop on a nearly daily basis beginning Wednesday.  As the event(s) near, I will be able to get more specific on what to expect out of these storms.  However at this time, a severe weather outbreak is not anticipated.

Stay tuned.

As most of you noticed, the MTW forum has been closed this week for upgrades.  During the downtime we have been evaluating site performance and have decided to move in a new direction for now.  This new direction does not include a forum in the immediate future, but we may bring it back in time.

Don’t worry … there are several new exciting features coming to MyTexasWeather very soon that will enhance the way Texans get their weather information! However, if you still have the need to discuss weather with us… check our Facebook, MySpace and Twitter!

Thanks,

Anthony

Whew… what a title! It was yet another awesome Spring day across South-Central Texas.  No rain fell again, but temperatures rose to a perfect 87 at the San Antonio International Airport Thursday afternoon with partly cloudy skies.

Thursday is also the day the latest Drought Monitor is released.  Bexar County remains in a chart-topping “Exceptional” D4 drought.  However, ther is some glimmer of hope as the D4 coverage has been cut in half in a weeks time.  Parts of Webb County near Laredo have been downgraded to D2, or “Severe” status; while areas south of town also improved to D3 status.  There are more chances for rain the next 8-days; so hopefully the drought will continue to diminish.  The Edwards Aquifer remains in somewhat decent shape as the latest reading of the J-17 Well was holding relatively steady at 654.0 ft above sea level.  This is still in Stage 1 Water Restrictions territory, but 4 feet over the trigger for Stage 2.  Barring any rain, Stage 2 would occur in about a weeks time.  Therefore, it is imperative that we do our best to conserve water.

We are tracking a couple interesting features that could play a factor in our weather the next couple of days.  First, there is a well-defined low pressure system in the Eastern Gulf of Mexico moving northwestward and a weakening “ridge” aloft.  At the same time, a surface low is forecasted to develop across the state by the weekend.  These factors combined will make it possible for some showers and thunderstorms to develop with the help of daytime heating.  I do not expect any widespread severe thunders due to the lack of any upper level dynamics. However, small hail cannot be ruled out — especially due to the high amount of instability already in place.   Rain chances this weekend remain around 30% for Sunday.

By Monday, winds will shift to the south/southwest drying out the atmosphere.  Dry air heats up fast, so expect the temperatures to sore early next week.  Right now the 8-day forecast has 100 for the high on Tuesday… I would not be surprised to see higher readings out west. The only caveat in this forecast is how much rain we recieve this weekend.  The more we see, the lower the probabilities of us reaching the century mark in town.  Otherwise, break out the sun screen and crank up the A/C… summer is here! (It wouldn’t be the first 100 degree reading this year though)

As me move towards the end of the next week.. computer models are still fairly undecided as far was what they want to predict.  The 12Z and 00Z suites want to activate yet another frontal passage across the region bringing additional opportunities for showers and thunderstorms.  For now, I’ll keep rain chances around 20% and increase/decrease the odds of precipitation as conditions warrant.

On one last note, NOAA and Dr. William Gray released their 2009 Hurricane Season Predictions.  Both groups are forecasting a near average season.  Of course, you can count on MyTexasWeather to keep a continuous eye on the tropics and warn of any threat to the Texas coast.

Stay tuned.

Another spectacular afternoon across South-Central Texas on Wednesday.  High temperatures topping in the mid 80s with clear skies and low relative humidity.  It is impossible to ask for anything better towards the end of May, no?

Unfortunately, yesterday was probably the last nice and cool day we will experience for quite a while… possibly even until the fall.  Atmospheric heights aloft are going to progressively weaken, which will in effect weaken the strong cap we have on top of us.  At the same time, computer models are bringing in a surface low across the state.  Both factors combined leave the possibility for some showers and thunderstorms to develop across the region mainly on Saturday, however some of the storms may linger through the overnight hours  Saturday night and into early Sunday morning.   Due to the lack of upper level dynamics, severe weather is not likely.  However we will have enough instability in place that some small hail cannot be ruled out in some of the storms that do develop.

Late Sunday and into the early portions of next week, the atmospheric heights rebuild and the winds will shift towards the west at the surface.  This will dry out the atmosphere both aloft and at the surface and add a compressional heating component.  Computer models are trending warmer for Monday and Tuesday, and our current 8-day reflects these changes.   Triple digit heat is certainly not out of the question.   The main mitigating factor will be how much rain we recieve this weekend as to how hot it will get early next week.  The wetter the soil, the more insulated our temperatures will remain.

As we move into the longer range, models show absolutely no agreement.  Some runs bring in deep troughs into the region and other runs promote ridging aloft.  Keep checking the latest blog updates for up-to-the minute weather information.

Stay tuned.

Let me begin this blog entry by saying how fantastic the weather has been the past couple of days.  Saturday we had widespread soaking rains across South-Central Texas adverting the inevitable Stage  2 watering restrictions by at least a week.  Behind the storms came in a dry cool airmass allowing temperatures to only top out in the low to mid 80s in the daytime with overnight lows in the 50s.  The storms also helped to reduce the thick layer of smog and smoke that came in part by the annual crop fires in Southern Mexico and Central America.

The weather pattern the next few days across South-Central Texas the next few days appears relatively quiet.  We will be dominated by a general west-to-east zonal flow aloft; which will allow for conditions to remain dry and warm.  The next chance for showers will be this weekend as a weak disturbance will move through the region. In addition, a weakening low pressure system in the gulf will continue to move westward into the region.  This will allow the possibility for some showers and thunderstorms to develop with the help of daytime heating.  However due to the marginality of the event, I have kept rain chances around 10% for now.

Moving into next week, there are signs of a strengthening ridge aloft on Monday and Tuesday  coupled with a dry south to southwesterly wind.  This will allow temperatures to heat up quickly and that is why the current 8-day forecast has highs in the mid-to-upper 90’s.  By late Tuesday into Wednesday, a front will move through the region leaving the possibility for some showers and thunderstorms.  Current rain chances are 10%, but that may increase with time.

Stay tuned.