Large and intensifying Hurricane Alex bears down on northeastern Mexico, South Texas

By: Dr. Jeff Masters , 2:23 PM GMT on June 30, 2010

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Hurricane Alex continues to intensify as it slowly bears down on the coast of northeastern Mexico. Brownsville long-range radar shows the spiral bands of Alex, which has dumped heavy rains of up to four inches in northeastern Mexico and near Brownsville, according to satellite estimates of rainfall. The Brownsville airport received 0.78" of rain in the hour ending at 8am CDT, and 0.61" in the hour ending at 9am CDT. Floods from Alex have already killed ten people--six in Nicaragua, and two each in El Salvador and Guatemala.


Figure 1. Snapshot of the Brownsville long-range radar showing Hurricane Alex approaching the coast.

The 7:12am CDT eye penetration of the Hurricane Hunters found a central pressure of 959 mb, a modest 2 mb drop from the reading four hours previous to that. They noted a very tiny eye, ten miles in diameter, with a gap in the northwest side. Tiny eyes like this tend to be unstable, and in the 9:05am CDT eye penetration, the Hurricane Hunters found that the inner eyewall had collapsed, and the pressure had risen 2 mb, to 961 mb. A new, much larger eye will form today as the day progresses. During these "eyewall replacement cycles", a hurricane will typically weaken a few millibars , and the strongest winds will spread out over a larger area as the hurricane conserves angular momentum. Thus, the hurricane still has about the same amount of destructive power, it is just spread out over a larger area. This tends to increase the hurricane's storm surge, but lessens the wind damage, since the extreme winds of the inner eyewall are no longer present. Satellite loops show a large, well-organized storm with increasing amounts of low-level spiral bands forming, and improving upper-level outflow. Data from last night's flight of the NOAA jet showed an unusually moist atmosphere surrounds Alex, so dry air is no longer a problem for it. It's a good thing Alex has less than a day before making landfall, or else is would be a large and very powerful major hurricane.


Figure 2. Visible light image of Tropical Storm Alex taken at 19:35 UTC (2:35 pm CDT) on June 29, 2010, by NASA's Aqua satellite. At the time, Alex was a tropical storm with 70 mph winds. Image credit: NASA.

Storm Surge
Traditionally, a storm's ranking on the Saffir-Simpson Scale--the familiar Category 1, 2, 3, 4, 5 rankings we always talk about--have also been used to quantify storm surge threat. However, large, weaker storms that cover a huge area of the Gulf of Mexico, like Alex, can generate a larger storm surge than a smaller but more intense hurricane with a higher Saffir-Simpson rating. Thus, the National Hurricane Center has formally discontinued use of the Saffir-Simpson scale to characterize storm surge, and is studying the possibility of issuing separate Storm Surge Warnings a few years from now. These would be in addition to their traditional Hurricane Warnings. To give us a better idea of a storm's surge potential, Dr. Mark Powell of NOAA's Hurricane Research Division has developed the Integrated Kinetic Energy scale to rank storms. The scale ranges from 0 to 6, and a parallel wind damage scale that runs from 0 to 6 is also generated. Alex had an Integrated Kinetic Energy of 2.6 on the 0 to 6 scale at 1:30pm CDT yesterday, and its destructive potential rating for winds was just 1.2. Thus, Alex's surge ranked alomst one-and-a-half categories higher in destructive potential than its wind. These numbers have probably increased by a full category since yesterday afternoon. NHC is giving a 40% - 60% chance of a storm surge of at least 3 feet affecting the Brownsville area, and 10% - 30% chance the surge will exceed 5 feet. In theory, a Category 2 hurricane moving WNW at 5 mph can bring a storm surge of up to 8 - 9 feet to the South Texas and northern Mexican coast.

Other Impacts
Alex is bringing bands of heavy rain to the coasts of Texas and Mexico, as seen on the Brownsville, Texas radar. Hurricane local statements with projections for how Alex will affect the coast are now being issued by the National Weather Service in Brownsville and Corpus Christi. Flooding damage from the expected 6 - 12 inches of rain from Alex will be the main concern. Wind damage is a lesser concern, since the core of Alex is making landfall in a swampy, sparsely populated region of Mexico. The combined wind, surge, and flooding damage from Alex may be similar to 2008's Hurricane Dolly, which hit near Brownsville. Dolly was a Category 2 hurricane offshore that weakened to a Category 1 hurricane with 85 mph winds when it made landfall, and did about $1 billion in damage. Dolly also generated two weak EF-0 tornadoes, and Alex is capable of generating a few tornadoes as well, according to the latest discussion from NOAA's Storm Prediction Center. The atmosphere is moderately unstable, there is plenty of moisture, and wind shear at low levels has been increasing this morning. The greatest threat for tornadoes will occur late this afternoon, on the right side of where the storm makes landfall.

Alex in historical context
Alex is the first June hurricane since Hurricane Allison of 1995. Allison briefly became a minimal 75 mph hurricane before weakening and hitting the Florida Panhandle as a tropical storm. Alex is the strongest June hurricane since Hurricane Bonnie of 1986, which had 85 mph winds. Bonnie was the first hurricane I flew into as a member of the Hurricane Hunters. Bonnie made landfall along the upper Texas coast, and caused less than $20 million in damage. If Alex strengthens to 90 mph winds, it will be the strongest June hurricane since Hurricane Alma of 1966, which had 125 mph winds as it skirted the Florida Keys. There have been only ten hurricanes in May or June since 1945; only four of these were major Category 3 or higher storms.

Track forecast for Alex
All of the models take Alex to the west or west-northwest into northern Mexico by early Thursday morning. However, the steering currents are fairly weak, and Alex could stall and move erratically at times today. I don't anticipate that this weakness in the steering currents will allow Alex to move northward and make landfall in Texas. After landfall, the ridge of high pressure forcing Alex westward should remain in place and strengthen, keeping Alex's remnants over northern Mexico for several days.

Intensity forecast for Alex
Alex is over a region of ocean with moderately high total ocean heat content . Wind shear has fallen to a low 5 knots, and is projected by the SHIPS model to remain in the low range, below 10 knots, through landfall. The combination of low wind shear, moderately high ocean heat content, and plenty of moisture should allow Alex to continue to intensify today. Alex's pressure is already characteristic of a Category 3 hurricane, but the storm is so large that it is taking time for the winds to catch up to the pressure falls. It is unlikely that Alex's winds will be at Category 3 strength at landfall, since the storm is undergoing an eyewall replacement cycle, and does not have time to build a tight inner eyewall with strong winds before landfall. A Category 2 storm at landfall looks more likely.

Elsewhere in the tropics
The latest run of the NOGAPS model predicts the formation of a tropical disturbance in the Western Caribbean on Monday. None of the other models is showing anything brewing over the coming seven days.

Wind and ocean current forecast for the BP oil disaster
Alex is generating very rough conditions over the Deepwater Horizon blowout location, with 6 - 8 foot waves and 3 - 4 foot swells. Strong southeast to south winds of 15 - 25 knots will blow over the oil slick region today through Thursday, according to the latest marine forecast from NOAA. The resulting currents will push oil to many protected bays and estuaries that haven't seen oil yet. In addition, the 1 - 2 foot storm surge Alex is generating along the Louisiana coast will act to push oil deep into some low-lying marshlands. While this oil will be diluted some by the wave action, the impact of the oil and accompanying toxic dispersants on the marshlands is of concern. The latest trajectory forecasts from NOAA and the State of Louisiana show oil will also move westward along the central Louisiana coast towards the Texas border. Winds will decrease to 10 - 15 knots Friday through Monday but remain out of the southeast, keeping the pressure on the regions of coast in Louisiana, Alabama, and Mississippi that are seeing oil hit their shores this week.

Resources for the BP oil disaster
Map of oil spill location from the NOAA Satellite Services Division
My post, What a hurricane would do the Deepwater Horizon oil spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
NOAA's interactive mapping tool to overlay wind and ocean current forecasts, oil locations, etc.
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Next post
Either Rob Carver or myself will do an update late this afternoon or this evening.

Jeff Masters

Hurricane Alex (LRandyB)
Weather inbound to Hurricane Alex.
Hurricane Alex
Hurricane Alex (LRandyB)
Weather inbound to Hurricane Alex.
Hurricane Alex
Hurricane Alex (LRandyB)
Flight deck view from a WC-130J Hurricane Hunter aircraft
Hurricane Alex

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Member Since: Posts: Comments:
Whatever Charleys final stats were.....is not the point..... The point is he strengthened quickly and was devastating.... People need to be prepared for the worst. A cat 3 storm is very much in the picture here!!!!!

And if it doesnt materialize, great..... but dont leave yourself vunerable if it does!
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64.3 knots (~ 74.0 mph)
Category One Hurricane

That is the first recon reading I've seen so far (missed a few missions though) of hurricane level surface winds.
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Quoting CaneWarning:


I evacuated Tampa and went to Orlando for Charley. Oops.
And my family and I stayed put... not even a drop of rain here in St. Petersburg that day... HOORAY!
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744. xcool
BAD HURRICANE
Member Since: September 26, 2009 Posts: 2 Comments: 15603


Member Since: July 3, 2005 Posts: 415 Comments: 125753
Alex trying hard to clear out his eye
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Quoting watchingnva:


click...anyone on this blog for info should contact their local ems for local direction...unless from the nhc, any thing like the above, is that persons personal opinion....take with a grain of salt...


Gee, reminds me of stormtop's forecasts for Gustav to hit NOLA a couple years back.
Member Since: August 26, 2006 Posts: 16 Comments: 4766
watching Oz.. holy crap.. did anyone else hear his ideas on getting into mexico? lol including the bounty hunter lol
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Oz is having so much fun it seems.
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Member Since: June 9, 2007 Posts: 4 Comments: 15718
Afternoon Pat, Flood. I see the same things going on today as last night.
Member Since: February 27, 2010 Posts: 0 Comments: 1125
any free links to live coverage anyone?
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Quoting Chicklit:
Hey, good afternoon. Is Cantore there yet?
Don't want to change the subject. Just want to keep you all up to date on what's happenen' further east. IRLoop

My guess is he was heading down to La Pesca to intercept, but got stopped at the border. He is what is pulling Alex into Brownsville! ;-)
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Quoting CyclonicVoyage:
Approaching 24.5 now

If I were sitting in Brownsville right now I would be saying to myself ummm where's the ridge, where's the ridge. Seems to have sped up some too.

Visible.
It's on radar now so throw looking at Sat pics out for the track.
Radar movement looks to be close to due west or at most 290deg since that last wobble 2 hours ago.
But being in the NE quadrant Brownsville is going to get some whuppin..
Member Since: September 1, 2009 Posts: 23 Comments: 1005
Quoting StormChaser81:


145mph

Actually, in the post-storm report, Charley's landfall intensity was bumped up to 130 kts, or 150 mph.
Member Since: August 2, 2006 Posts: 45 Comments: 11569
Quoting hurrkat05:
ALEX IS DRIFTING TOWARDS THE NNW LIKE A CRAWL IN THE LAST 3 HOURS..STEERING CURRENTS NEED TO CHANGE BY TONIGHT ARE ALL BETS ARE OFF FOR ALEX MAKING LANDFALL..YOU PEOPLE IN SE TEXAS AND SW LA SHOUD PAY VERY CLOSE ATTENTION..YOU NEED TO HAVE EVERYTHING READY IN CASE YOU HAVE TO MOVE QUICKLY..I WILL HAVE MUCH MORE INFO THIS AFTERNOON AT 5PM..ALEX CONTINUES TO STRENGTHEN..


click...anyone on this blog for info should contact their local ems for local direction...unless from the nhc, any thing like the above, is that persons personal opinion....take with a grain of salt...
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Quoting weatherboyfsu:
I went thru Charley here in Orlando..... Couldnt make it to the coast because of the uncertainty of where he was going to make landfall. Charley was still a formidable storm in Orlando. We had wind gust over 100 mph at the Orlando Executive Airport.


I evacuated Tampa and went to Orlando for Charley. Oops.
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Quoting JamesSA:
I can't bear to even watch someone like Oz. He is like one of those old Chevy Chase movies, going from one self inflicted catastrophe to the next. They were painful to watch, but they at least had a happy ending. I'm not so sure about our friend Oz.

I feel sorrier for his wife.
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629
WFUS54 KBRO 301706
TORBRO
TXC489-301730-
/O.NEW.KBRO.TO.W.0008.100630T1706Z-100630T1730Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1206 PM CDT WED JUN 30 2010

THE NATIONAL WEATHER SERVICE IN BROWNSVILLE HAS ISSUED A

* TORNADO WARNING FOR...
WESTERN WILLACY COUNTY IN DEEP SOUTH TEXAS.

* UNTIL 1230 PM CDT

* AT 1206 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
TORNADO 8 MILES NORTHEAST OF RAYMONDVILLE...MOVING SOUTHWEST AT 50
MPH.

* THE TORNADO WILL BE NEAR...
YTURRIA.
RAYMONDVILLE.
LYFORD.
LASARA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PLEASE REPORT TORNADOES OR FUNNEL CLOUDS...WINDS OF 58 MPH OR
HIGHER...HAIL THE SIZE OF PENNIES OR LARGER...AND ANY WIND DAMAGE TO
YOUR NATIONAL WEATHER SERVICE IN BROWNSVILLE BY CALLING 956-504-1432.
Member Since: July 3, 2005 Posts: 415 Comments: 125753
lol i hope he is aware that alex might heading his way
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Quoting msglfcst:


Landfall at night makes it more anxiety producing. Camille was worse for my area due to a landfall during night; compared to Katrina who landed during the day. Just my opinion.


I remember sitting in the living room during Ivan at about 11PM going "Man, this is really bad, we must be in the eyewall." And then between midnight and 2AM all hell broke lose. Windows blew out on the second floor, roof started to peel off, sounded like a 747 taking off on the roof for about 2 hours. Just relentless. Sleep was out of the question.
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I went thru Charley here in Orlando..... Couldnt make it to the coast because of the uncertainty of where he was going to make landfall. Charley was still a formidable storm in Orlando. We had wind gust over 100 mph at the Orlando Executive Airport.
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Floater - Rainbow Color Infrared Loop
Member Since: July 3, 2005 Posts: 415 Comments: 125753
Quoting Jedkins01:



I live in Clearwater Florida, that was the forecast discussion out of the NWS at TBW.

I'm just excited because this June, like June last year has been mostly horribly hot and very lame for wet season standards. Hopefully the pattern this week will be a sign of the next 3 months, very wet and stormy like last year.


OK, thanks, didn't recognize the AFD.
Looks like you may get your wish.
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Hey, good afternoon. Is Cantore there yet?
Don't want to change the subject. Just want to keep you all up to date on what's happenen' further east. IRLoop

Meteostat
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Quoting winter123:


No joking around, this is looking like a pinhole eye.


That's what I just said!
Member Since: August 30, 2008 Posts: 8 Comments: 2834
Streaming Oz to my Android phone using USTREAM viewer looks even better... heck I'll have him on when driving home from work if he's still broadcasting.
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Quoting Progster:

Where are you?



I live in Clearwater Florida, that was the forecast discussion out of the NWS at TBW.

I'm just excited because this June, like June last year has been mostly horribly hot and very lame for wet season standards. Hopefully the pattern this week will be a sign of the next 3 months, very wet and stormy like last year.
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I can't bear to even watch someone like Oz. He is like one of those old Chevy Chase movies, going from one self inflicted catastrophe to the next. They were painful to watch, but they at least had a happy ending. I'm not so sure about our friend Oz.
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Quoting Patrap:
Brownsville is the Impact area from the Onshore flow..

Take cover and stay indoors .

The Storm is now beginning in earnest and the effects are being felt as far away as New Orleans.



Landfall at night makes it more anxiety producing. Camille was worse for my area due to a landfall during night; compared to Katrina who landed during the day. Just my opinion.
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Man, Port Isabel and Brownsville are about to get pummeled with another round of very heavy rain. I expect the wind gusts will be decently higher in this band as well.
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Quoting weatherboyfsu:
Anyone remember Hurricane Charley???????? I do... He crossed over Cuba and the NHC predictions were 100-115 mph...... Guess what? 140 mph and peeps were heading for the hills in florida.....Good luck!


145mph
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AAh, I'm tired of getting the 50th comment and therefore getting ignored! I have a knack for it lately.
...


No joking around, this is looking like a pinhole eye.
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Quoting GBguy88:


I don't know that I've ever heard of a mandatory evac for a category 1. In the Keys maybe? Or New Orleans?
Nope, at least not in New Orleans.
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Member Since: July 3, 2005 Posts: 415 Comments: 125753
705. xcool
POOR ROB HOLD HOLD ON
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Anyone remember Hurricane Charley???????? I do... He crossed over Cuba and the NHC predictions were 100-115 mph...... Guess what? 140 mph and peeps were heading for the hills in florida.....Good luck!
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Quoting WaterWitch11:
i don't understand why oz would drive on to the sand and risk being stuck. i can't believe that business will not let it's workers go home. the thought process of some people, blows my mind.

you get one life, use it wisely.


I was living in Ft Walton beach, FL working for a roofing company (sales). The owner had 6 roofs loaded with materials the day before Dennis was to make landfall. The next day he calls everyone to help unload all the roofs with >30mph winds since Dennis was making landfall near Navarre Beach. I told him good luck.
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These are flight level winds,
96 knots
(~ 110.4 mph)

Translates down to about 90 at the surface.
Member Since: July 8, 2005 Posts: 259 Comments: 23018
Quoting kmanislander:


I don't believe so.
I thought i had read about a trough earlier but i wasnt sure if it was the one that had already passed or a new one that might have some influence on Alex?
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.
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Quoting PensacolaDoug:
Oz has guts.

More guts than brains sometimes!


It takes some intelligence and imagination to be afraid of something; you have to be able to imagine what the worst case scenario could be...

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698. IKE
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.