What caused the recent devastating and deadly flooding in Texas, Oklahoma and other states? One thought, advanced by Accuweather and others, is that the developing El Nino played a role. As we’ve written before, an El Nino is warmer than expected waters in the Pacific Ocean. El Nino events result in a split jet stream and it the southern stream likely contributed to the flooding in the South. Typically, heavier than normal rains occur in Spring, Autumn and Winter of El Nino years in a swath from California into the Mid-South.
Historically, even weak and/or developing El Ninos can cause the extreme precipitation witnessed in May. California largely missed out although the area around San Diego picked up record rainfall. In past El Nino events California received most of its precipitation during winter months. It remains to be seen if the current event will last that long.
In the meantime drought conditions have been greatly lessened in Texas, at least in the short term. Of course that came with a terrible price…dozens of deaths and hundreds of millions of dollars in damage. The toll continues to rise and many rivers remain in flood.
EDEN Flood Resources:
It’s been an eventful week on the weather front, so let’s highlight a few points.
What started out as a very quiet first quarter of the year as regards the number of tornadoes has become much more active since mid-April. There have been several widespread, damaging and deadly outbreaks, especially over the last ten days or so.
In addition, the storms over the past weekend (May 9 and 10) included extremely high rainfall rates in some areas which led to flash flooding and necessitated swift water rescues. Some of the rescues were broadcast live by television stations in Dallas and retransmitted to the entire country via The Weather Channel.
And if that wasn’t enough, a late season snowstorm on the same weekend buried parts of the Rocky Mountains into the Dakotas. The heavy, wet snow damaged buildings and had to be shoveled out of Coors Field before the Colorado Rockies could host their Sunday afternoon game against the Los Angeles Dodgers.
And to top it all off, Tropical Storm Ana, brought gusty winds and copious amounts of rain to the Southeast.
NOAA’s Climate Center has issued its 2015 Spring Outlook covering flood potential, precipitation, temperature and drought through the April-June period. The flood outlook is for mid-March to Mid-May.
According to the outlook, the greatest potential for Spring flooding is in the Northeast along with a portion of the lower Missouri River and other nearby rivers and streams in parts of southern Illinois, southwest Indiana and far northern Kentucky. The near term potential is being driven by snow melt. That melt will also influence the somewhat longer term in that soil moisture will be above average to far above average in those areas.
As for temperatures, much of the eastern two-thirds of the nation will experience near-normal temperatures with the West Coast being much above normal. Only portions of Texas and New Mexico are forecast to be below normal.
The outlook calls for above-normal precipitation in the Southeast and the Four-corners area with below normal precipitation in the Pacific Northwest and parts of Minnesota and Wisconsin. The rest of the country will be near normal.
Drought conditions will continue or worsen in much of the western third of the country and drought may also spread from Minnesota into Wisconsin. The drought will improve in eastern New Mexico and Oklahoma. 40% of California is already in an exceptional drought and the predicted hot temperatures and lack of precipitation will exacerbate that situation.