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Emily makes landfall

By: Dr. Jeff Masters, 1:15 PM GMT on July 20, 2005

The eye of Hurricane Emily made landfall at 635 am CDT this morning along the northeastern coast of Mexico about 3 miles south of Boca Madre, which is 75 miles south of Brownsville, Texas. Emily had 125 mph winds and a central pressure of 944 mb at landfall, making it a Category 3 hurricane.

Emily managed to hold together and not weaken after yesterday's rapid intensification cycle. I had speculated that the slow movement of the hurricane would stir up cooler waters and cause weakening, and that the cooler waters next to the coast might also weaken the storm. That did not happen, apparently since the other environmental factors (weak wind shear, good upper level outflow) were strong enough to overcome the cooler waters. Mexico was unfortunate to have the storm slow down and make landfall at peak intensity. The slow motion of the storm means that the coast will be exposed to a long period of high water and battering waves. However, this portion of the coast is sparsely populated. Browsville is just north of the area of hurricane force winds, but the coastal areas will take a severe pounding from Emily's storm surge. The rains of Emily, expected to bring 2 - 4 inches to South Texas, will be most welcome, as this part of Texas is under extreme drought.

Emily was undergoing a eyewall replacement cycle at landfall. If one looks at the last VORTEX report from the Hurricane Hunters, one sees the item: "M. CO15-50". This means concentric eyewalls, with the inner eyewall 15 nautical miles in diameter and the outer eyewall 50 nautical miles in diameter. This is the situation that happened several times during the course of both Emily's and Dennis' lives. As a hurricane intensifies and spins tighter and tighter, the eyewall contracts until it is no longer stable and collapses, and a new outer eyewall takes over. I've annotated a radar image below to show the concentric eyewalls of Emily at landfall.



The Brownsville 248 nm mile range radar will be interesting to watch today as Emily moves inland and the eyewalls collapse.

Dr. Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

"I had speculated that the slow movement of the hurricane would stir up cooler waters and cause weakening, and that the cooler waters next to the coast might also weaken the storm. That did not happen, apparently since the other environmental factors (weak wind shear, good upper level outflow) were strong enough to overcome the cooler waters."

Quote from another discussion board from last night:

"Emily has only been in the region for a couple of hours, while research has shown the lag time for upwelling to be a major concern is closer to a day. Recall Frances -- over shallower warm waters than these -- took about a day to really begin spinning down before moving towards Florida. Roxanne in 1995 was able to maintain itself for several days before finally weakening over its own upwelled waters.

Sea surface temperatures are around 30C in the vicinity of the storm with the depth of the 26C waters extending down to about 60-80m. As further research has shown, storms of category 4 intensity generally affect the oceans down to about 70m -- 45m for the greatest mixing -- meaning that any negative impacts are likely to be minimal, even if the storm were to sit there all night long. A (much) more likely culprit of any weakening is likely to be entrainment of dry air off of the Mexican plateau/landmass, but that doesn't appear to be playing a role at this time. I do agree that this storm isn't the easiest to predict, but I don't agree that upwelling is going to play any significant role unless the storm sits there until this time tomorrow."
making a bee line to monterrey, mexico..with orographic lifting,this could be disaterous.
yes, alot of rain will be rung out and the slow motion should continue. lots of mudslides in the works.
rio grande....will be worlds longest water slide if it dont clear area fast..
Is there a sight with radar and Mexican landmarks detailed (e.g. Monterrey)? Thanks
Link
Link

oops...sent too soon last time
oh well

http://www.srh.noaa.gov/radar/loop/DS.p20-r/si.kbro.shtml
thanks that helps. Anything more detailed? Anywhere?
you know something.....I never noticed if the mexican goverment put warning out for the second landfall...that would be bad some may have been taken by surprize,some could pick up american broadcast,but with the standard of living alot did not...
Conditions at PTIT2 as of
(9:06 am CDT)
1406 GMT on 07/20/2005
Atmospheric Pressure (PRES): 29.70 in

I think emily ate some instuments all they have is a barometer...I know she ate a bouy it washed up on padre Isle...
CNN showed early this morning local authorities in Monterey warning people and asking people living on the river to evacuate
Mexico is not as backwards as it used to be
not as backwards......but still bad or the border would not have such an influx
No doubt, out
http://seaboard.ndbc.noaa.gov/show_plot.php?station=42020&meas=sght&uom=E
nice waves 50 nm SE of Corpus
its amazing emilys eye is holding together very nicely considering what she is over now...
Hindcast
This was my first prediction re Emily

Posted By: fredwx at 11:05 AM EDT on July 12, 2005.
The latest data seems to suggest that the Bermuda-Azores High will remain strong and take Emily towards Texas or Mexico. The historical data suggests this as well as it is not likely to recurve in the presence of the prevailing strong subtropical ridge.
Here was my next post July 13th regarding Emily's track

Posted By: fredwx at 8:03 AM EDT on July 13, 2005.
As I posted yesterday, I think Emily still looks like it will track towards a MEX/TEX landfall. Emily could turn northward over NW Caribbean but it is too early to tell.
Reasoning:
1. Climatology - Historicly limited data for July suggests that those storms that develop either recurve east of Florida (which is unlikely here) or continue across the Caribbean into Mexico or turn NW-N towards Texas. There was one (1887) in late July that turned North to hit western Florida panhandle (Hope Emily does not take that track as those folks have already had their share)
2. Azores-Bermuda high forecasted to build or at least hold throgh this weekend.
theres an old fishermans wise tale that states "if they pass 92 then they are through"....92 meaning longitude..
Stormtop, yes the well-defined circulation six hours after landfall is amazing. However Emily hasn't reached the higher elevations yet. She is still over land that is only 50-200m in elevation and right now (11:45 CDT) is moving along a river plain south of Mendez. She won't start to hit the higher elevations for another 50 mi inland, in about another 4-5 hours.
on the monterrey,mexico official gov. site,not one mention of Emily ....
it would not be that the water is cooler,it would be the slope of the shelf,its easier for a hurricane to "upwell" shallower water.N.Gulf coast has more slope....wher texas coast drops off faster.
Come august on North gulf coast the land mass will be warmer and the shallow water wont be cooled by the land mass....so early months of hurricane season due to slope of shelf,the shallow water near land mass is cooler.
104 octane at that!...the whole gulf is from now through early Oct...
funny not many blogs since landfall,and now is when it gets interesting .Orographic lifting and the deterioration by altitute of a hurricane...
I think its about time they shifted one of the floaters views to the SE Bahamas...looks like we may have a new one,last satellite image looks as if a stucture is taking place.
Hello all, im new to the site, but love the tropics coverage and the blogs, even though I live near Dr. Jeff, in Ann Arbor, i still love to study weather. It's about time we reached a bit of a lull this season, i don't see anything too favorable right now, but this season will be active for sure. Now is the time to take a good breather.
Its starting to look like here we go again.
Still hot and humid in Houston we're getting rains every once in a while - nothing major
Looks like a Td off the southeast Bahamas.
Yeah, I saw that depression earlier. I do not know much about these weather patterns yet, but I found it a little suspect.
Where do you think it will go?
wnw,across south florida or through florida straits..may clip the keys.Eastern Gulf is where is headed..
Whatever becomes of that mess is unlikely to hit the coast
We need some rain here on tha GA coast, so hopefully it will bring us some.