Tropical Weather Discussion...On the anniversary of one of the worst storms to ever strike the U.S., and the strongest and deadliest June storm ever, Hurricane Audrey, we are closely monitoring the progression of another Gulf storm tonight. Hurricane Audrey struck SW Louisiana on this date 53 years ago as a category 4 storm with winds around 150 mph, and a 12-15' storm surge. Over 500 people perished in the storm, and the exact death toll is still not known to the this day. Tonight, our focus continues to be on the season's first named storm, Alex. not much has changed since the 4p.m. forecast package.
Tropical Storm Alex Advisory
...Alex gaining strength over the Gulf...now a Tropical Storm once again...future track still a bit uncertain...
10p.m. CDT Sunday, June 27, 2010
Latitude: 19.4 N
Longitude: 91.3 W
This position is 60 miles WSW of Campeche, Mexico or about 470 miles ESE of Tampico, Mexico.
Winds: Increased to 45 mph with higher gusts. This makes Alex a tropical storm once again. Alex is a very large tropical storm. Tropical storm force winds extend outward 175 miles from the center of circulation. Strengthening is forecast for the next couple of days. Alex is forecast to become a hurricane in 36-48 hours.
Movement: WNW or 300 degrees at 7 mph. Alex's forward speed has decreased, and a general NW motion is expected through Tuesday.
Minimum Central Pressure: The pressure has decreased to 991 mb. or 29.26". Pressure will continue to fall for the next 24-48 hours, and the strengthening trend will continue.
No new watches and warnings are in effect.
Rainfall totals of 4-8" with isolated amounts up to 15" in mountainous areas are expected through Monday across Southern Mexico, the Yucatan Peninsula, and Guatemala. Life-threatening flash floods and mudslides are expected across this region as well.
Discussion...There is not a whole lot more to add from the 4p.m. Sunday discussion. The intensity forecast has changed a bit based on the fact that Alex is already a tropical storm once again. The storm continues to exhibit good, strong structure on visible satellite. Alex is a very large tropical cyclone, and will only grow larger over the next couple of days. Rain band from Alex will spread towards the Northern and Central Gulf coast this week. The intensity forecast now calls for Alex to reach category strength with winds around 95-100 mph at peak intensity on Wednesday before landfall. The current projected landfall is forecast to be in Northern Mexico, however, models continue to shift further right, and many forecast models tonight are clustered between the Rio Grande and Corpus Christi. There is still much uncertainty as far as how the storm will behave in relation to the large scale synoptic features I discussed in depth at the 4p.m. discussion. Scroll down for the detailed description. The Gulf coast ridge is weakening, and up to this point Alex has been steered around the Southern periphery of the controlling ridge. Now, that the ridge is weakening there is some wonderment if Alex will begin to move more to the North or keep on a more southerly track into Mexico. The possibility of a more Northern track seems to be increasing tonight. The new official forecast track doesn't really reflect this, but if model trends continue on Monday, I would expect further forecast revisions to be made.
It remains to be seen how much influence the developing weakness will have on Alex, but it appears that it will at least temporarily affect its movement. The steering currents that have kept Alex on a steady WNW pace are weakening and nearly collapsing tonight. It is possible that Alex could stall out for a time over the Gulf waters during the next couple of days. The environment over the Southern Gulf is certainly one that is conducive for further development, and the idea of Alex becoming a hurricane by Tuesday certainly looks to be realized. The current projection of a category 2 storm at landfall could even still be a bit conservative especially if the storm stalls out or treks further North, but based on the consensus of the models a storm of category 2 intensity seems logical for now. The other factor that may or may not pull Alex further North is on the map tonight as well. This is in the form of a rare summer cold front which has its sights set on approaching the Gulf coast by mid-week. The front and associated trough will most definitely be weakening by this time, but it could still be strong enough to have an influence on Alex especially if the weakness pulls Alex northward. This would increase the threat to SW Louisiana, and the outliers from the model suite do still depict this idea. Alex looks very impressive on satellite tonight, and with the explosion of storms near the center or the CDO (Central Dense Overcast), it is possible that Alex will be nearing hurricane strength Monday morning. It appears that Alex is primed for a period of rapid intensification. Therefore, I believe the official intensity forecast will be nudged upward. I also believe that ultimately the official landfall forecast will be shifted further to the right. I believe landfall will be in the U.S., but its still too early to tell for sure where it will occur, and how much the threat to SW Louisiana will increase with a landfall on the Texas side of the Rio Grande. Landfall is projected for Thursday, but if it comes in further North it could be as late as Friday. The current forecast suggests the landfall in Northern Mexico on Thursday. There will be some effects across our area because we will have a strong onshore flow with the storm to our SW. These effects appear minimal at this time with just a better chance of rainfall each day this week as some squalls from Alex rotate around the circulation. Some coastal flooding and an increase in winds and seas over the coastal waters is expected as well. More fine tuning will occur in the days ahead. More model data will hopefully help establish a better forecast consensus on Monday. It's still just a watch and wait mode around these parts, and that's exactly what I urge everyone to do. The graphic suite follows.
That's all for this update. The National Hurricane Center's next update will be at 4a.m. CDT Monday. My next storm update will be after the 10a.m. advisory Monday. Be sure to check back here for all the latest details on the season's first tropical system. Feel free to leave your questions or comments right here on the blog or send me an e-mail at the address provided on this page.
Have a great Sunday night & Monday! God bless!
-DM-
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