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Hurricane Barbara Hits Mexico; Severe Weather Outbreak Continues in Midwest

By: Dr. Jeff Masters, 3:29 PM GMT on May 30, 2013

The Eastern Pacific's Hurricane Barbara is still alive as a tropical depression at the edge of the Atlantic's Gulf of Mexico, and has the potential to gain new life as an Atlantic tropical cyclone later today. Barbara made landfall near 4 pm EDT (1 pm PDT) May 29, 2013, on Mexico's Bay of Tehuantepec coast, as a Category 1 hurricane with 75 mph winds. The storm killed two people, and brought heavy rains of 16.02" (407mm) to Arriaga in the state of Chiapas in an 18-hour period. Barbara remains a serious rainfall threat today. The storm intensified remarkably rapidly, becoming a hurricane just 21 hours after it became a tropical depression. According to NOAA's Historical Hurricane Tracks website, only one other Eastern Pacific hurricane has ever made landfall in May--Category 1 Hurricane Agatha of 1971, which hit Mexico west of Acapulco. Barbara is just the 2nd hurricane ever to make landfall in the Bay of Tehuantepec (the other: Category 1 Hurricane Rick of 1997.) Barbara's formation date of May 28 was the 2nd earliest appearance of the Eastern Pacific's 2nd named storm of the year; the record earliest second storm of the year occurred just last year, on May 21, 2012 (Tropical Storm Bud.) The average date for the formation of the Eastern Pacific's 2nd storm is June 25. Barbara's landfall location was the most easterly on record for an East Pacific hurricane. Records of Eastern Pacific hurricanes go back to 1949, but aren't really reliable until 1966.

Figure 1. MODIS satellite image of Hurricane Barbara taken at 4:30 pm EDT on May 29, 2013. At the time, Barbara was making landfall as a Category 1 hurricane with 75 mph winds. Image credit: NASA.

Barbara survived its overnight crossing of Mexico's Isthmus of Tehuantepec with its circulation intact, but lost nearly all of its heavy thunderstorm activity. This morning, the center of Barbara was located just inland from the southernmost waters of the Gulf of Mexico's Bay of Campeche. Barbara was drifting northwest, towards open water, at 3 mph. With wind shear a moderate 10 - 20 knots over Barbara, the storm has the potential to be classified as an Atlantic tropical depression later today if its center emerges over water. However, latest satellite loops have shown a steady reduction in the storm's heavy thunderstorms this morning, and Barbara may lose its circulation before it has time take advantage of the Gulf of Mexico's warm waters. Since Barbara is a small storm, the moderate wind shear may be too great for it to withstand. None of the reliable computer models predict that Barbara will survive into Friday. If Barbara is able to re-intensify to a tropical storm, it would keep the name Barbara, becoming the first Atlantic storm ever to have an Eastern Pacific name. Formerly, Eastern Pacific storms crossing into the Atlantic would be given a new name, but a recent NHC policy change allows storms to keep their names when they cross from one ocean basin to another. If Barbara were to dissipate before reaching the Gulf, then its remnants regenerate into a tropical storm in the Gulf, it would be named Andrea. If you want to discuss this year's hurricane season via Twitter, AP will be doing a hurricane twitter chat today (Thursday) at 1 p.m. EDT: #APStormChat; the National Hurricane Center is doing a hurricane chat at 2 pm EDT: #HurriChat.

Double ocean tropical cyclones: a rare breed
According to the Hurricane FAQ, since 1923 there have been four East Pacific tropical storms or hurricanes that have maintained their circulations while crossing into the Atlantic Ocean, becoming tropical storms in the Atlantic Ocean:

Northeast Pacific Tropical Storm Alma (May 2008) became a remnant low in the Atlantic, where it merged with another tropical wave which generated Atlantic Tropical Storm Arthur. Arthur hit Belize as a tropical storm, killing nine and doing $78 million in damage.

Northeast Pacific Hurricane Cosme became Atlantic Tropical Storm Allison in June 1989. Allison hit Texas as a tropical storm, and heavy rains from Allison--up to 30" in some regions of Texas and Louisiana--triggered floods that killed eleven people and did $1 billion in damage. (A later incarnation of Tropical Storm Allison in 2001 also hit Texas, and caused such extensive flooding that its name was retired.)

An unnamed Northeast Pacific Tropical Storm (September-October 1949) became Atlantic Hurricane (Storm #10) and hit Freeport, Texas as a Category 4 hurricane, killing two people.

An unnamed Northeast Pacific Tropical Storm (October 1923) became Atlantic Hurricane (Storm #6) and made landfall as a Category 1 hurricane in Louisiana.

There have been eight Atlantic tropical storms or hurricanes that have maintained their circulations while crossing into the East Pacific Ocean, and were then tropical storms in that ocean.

Figure 2. Severe weather outlook for Thursday, May 30, calls for a "Slight Risk" of severe weather over much of the Midwest. You can follow today's severe weather outbreak from our Severe Weather page.

Multi-day severe weather outbreak in the Midwest brings more tornadoes and flooding
It was an active day for tornadoes in the Midwest on Wednesday, with NOAA's Storm Prediction Center (SPC) logging 23 preliminary tornado reports. Twisters touched down in Nebraska, Kansas, Texas, Oklahoma, Iowa, and Wisconsin. The tornadoes missed heavily populated areas, and no injuries and only minor damage was reported. The latest forecast from NOAA's Storm Prediction Center call for a "Moderate Risk" of severe weather today (Thursday) over much of Oklahoma, with the potential for several strong EF-2 and EF-3 tornadoes.

Figure 3. Five-day rainfall forecast for the period ending at 7am EDT Tuesday, June 4, calls for very heavy rains of 3 - 5" over much of Missouri. Image credit: NOAA/HPC.

As discussed by wunderground's weather historian Christopher C. Burt in his latest post, Some Phenomenal Rainfalls the Past Week in the U.S., the country has seen a lot of very heavy rainfall over the past week that has caused serious flooding. Of particular concern is Iowa, where Governor Terry Branstad issued a disaster proclamation on Tuesday for 13 Iowa counties, due to recent storms and flooding.The Iowa State Climatologist, Harry Hillaker, announced on May 29th that this has been the wettest spring (March-May) on record for the state since records began 141 years ago. A state average of 16.4” has been preliminarily reported. The previous wettest spring was 15.5” way back in 1892. He warned that “Iowa is at a tipping point for a major flood event”. Rains of 1 - 2" are expected over Eastern Iowa the remainder of the this week, which will keep most rivers above flood stage. Another round of rains of 1 - 2" are likely on Tuesday and Wednesday of next week, when the next storm system rolls through. That system also has the potential to bring a severe weather outbreak to the Midwest.

Jeff Masters

Hurricane Flood Tornado

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