Tropical Weather Discussion...Alex is nearing his landfall point in NE Mexico, and that's a good thing of course. He has been strengthening at a fairly significant pace this afternoon and evening, and if he wasn't about to run out of real estate, we most likely would be looking at a major hurricane at landfall. As it is, a category 2 storm is still quite a formidable hurricane. This will be my last full update and discussion Alex since landfall will be occurring within the next couple of hours. A bit of a historical note here, Alex is the first June hurricane in the Atlantic Basin since Allison in June 1995. The latest advisory on Hurricane Alex follows.
Hurricane Alex Advisory
...Season's first hurricane, category 2 storm, Alex, to make landfall shortly just South of the Rio Grande...South Texas to experience strong Tropical Storm conditions...
8p.m. CDT, Tuesday, June 30, 2010
Latitude: 24.3 N
Longitude: 97.5 W
This position is near the coast of NE Mexico, about 40 miles NNE of La Pesca, Mexico and 110 miles S of Brownsville, Texas. The eye of Alex is about 15 miles from the closest point on the coast of NE Mexico.
Winds: 100 mph w/ higher gusts. Alex is a strong category 2 hurricane on the Saffir-Simpson scale. Alex has been in a steady state strengthening phase this evening, but the storm is just about as strong as its going to get because it will be making landfall shortly. This will end any chance of further strengthening because Alex will be out of contact with the warm Gulf waters. Weakening will begin shortly after landfall. Alex will dissipate over Mexico by the weekend. Alex is a large tropical cyclone, and hurricane force winds now extend outward to 70 miles from the center of circulation, while tropical storm force winds extend outward to 205 miles from the center primarily on the NE side.
Movement: W or 270 degrees @ 10 mph. Alex's forward speed has slowed a bit as it approaches landfall. The general Westward motion will continue over the next few days. Some fluctuations in forward speed are possible as the storm spins down over the mountains of Northern Mexico. On the current track, the eye of Alex will make landfall in the next hour or so. The storm will travel a route parallel to the Rio Grande until it spins down by the weekend.
Minimum Central Pressure: 27.99" or 948 mb. This pressure is actually equivalent of a strong category 3 or low end category 4 storm, thankfully the winds never caught up to the pressure or Alex would have been much stronger.
Watches/Warnings...No changes to the ongoing watches and warnings for Texas and Mexico. The Hurricane Warning remains in effect from Baffin Bay, Texas to La Cruz, Mexico. A Tropical Storm Warning is in effect on either side of the Hurricane Warning from Baffin Bay, Texas to Port O'Connor, Texas and from La Cruz, Mexico to Cabo Rojo, Mexico. The Hurricane Warning will likely be changed to a Tropical Storm Warning
later tonight as Alex begins to weaken after landfall.
Rainfall...Rainfall accumulations of 6-12" are expected across Deep South Texas and Northern Mexico. Isolated amounts of 20" are possible in these areas. These rains will likely cause life-threatening flash floods and mudslides especially in mountainous areas. Closer to home, rainfall totals of additional 2-4" are expected through Friday with the far outer rain bands of Hurricane Alex. Some localized flooding is possible.
Storm Surge...A dangerous water rise is expected along and to the North of the eye. Surge levels of 4-6' are expected along the coast. Near the coast, the surge will be accompanied by large and destructive waves. Closer to home once again, tide levels will remain high with tides running about 2' above normal. Some minor coastal flooding is expected through Thursday. The strong South winds will cause some tidal backup into the lower end of area rivers.
Wind...Hurricane force and tropical storm force winds have reached the coastline of South Texas and Northeast Mexico. Across our area, occasional gusts to near 30 mph will be possible through Thursday in the passing squalls. The hurricane and tropical storm force winds will gradually diminish across the strike zone after the storm makes landfall.
Tornadoes...Isolated tornadoes are expected across Northeast Mexico and Deep South Texas through Thursday.
Discussion...This will be my last full update on Alex since the storm is at landfall. Alex will certainly go down as a notable June storm. The pressure almost equals that of Hurricane Audrey for the lowest recorded pressure ever for an Atlantic Basin hurricane in the month of June. It is also the first June hurricane since Allison 1995, not to be confused with 2 very wet Tropical Storm Allisons in 1989 and 2001 which led to memorable flood events. Alex is going to make landfall in a sparsely populated area of NE Mexico, so most of the worst of the winds and surge will be in this area...some good news. Certainly, Alex will provide for a decent blow to Deep South Texas with strong tropical storm conditions. South Padre Island has been evacuated at a prime tourist time. The biggest impacts for the U.S. will be heavy rains and potential freshwater flooding as Alex continues to move inland and spin down over the next few days. A deep surge of tropical moisture will continue to rotate into land areas from the Gulf of Mexico with rain bands far reaching from the center of circulation. Rain bands from Alex have extended as far East as the Panhandle of Florida at times. The potential for catastrophic flooding exists over the mountains of Mexico including the Monterrey area. With landfall imminent, model data is essentially no longer needed at least for trying to figure out a landfall location. There is still some question about the future of Alex as it decays. Some models suggest it will slow down or stall out producing prolific rainfall totals in the Rio Grande region, while other suggests a steady movement off to the W or WNW leading to its eventual death over the mountains of Mexico. Alex is being steered around the periphery of a large ridge of high pressure to its NE. For now, the official forecast will depict a steady Westward progression with the storm totally decaying by the weekend.
The impacts of Alex on our area are already being felt with the off and on squalls, showers, and occasional thunderstorms. This will continue through Friday, although conditions will begin improving by Friday as Alex moves further inland and further away from our area. Minor coastal flooding and occasional gusts of wind to near 30 mph in the strongest squalls will be about the extent of the effects here. A Coastal Flood Advisory and a Flash Flood Watch remain in effect for our area. The Flash Flood Watch is for areas and along and South of the I-10 corridor. Rainfall totals by week's end should be on the average of 4" with totals of over 6" possible in isolated locales. The highest totals for the storm will come near the coast and over the coastal waters, and locations further North will see the smallest amounts. The eye of Alex is visible on the Brownsville (KBRO) radar, and this will be used in determining exactly when landfall occurs. I will attach links for the KBRO radar and a visible satellite image in motion, so you can watch the storm move inland.
Alex Visible Satellite
Brownsville, Texas Radar
That's all for now. I will post information on Alex for the next couple of days until the storm is officially declared dead. The National Hurricane Center's next update will be at 10p.m. CDT. Landfall has just occurred around 9p.m. with 105 mph winds near the municipality of Soto La Marina in NE Mexico. Please check back shortly for the regular forecast discussion, including the all important 4th of July weekend forecast. The blog will remain in storm mode through Friday.
Have a good evening and God bless!
-DM-
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