Major Flash Flood Threat Looms From Gulf Coast to Mississippi Valley

For the third time in less than a month, a threat of flash flooding looms in parts of Texas and Louisiana in the week ahead. This time, however, the flood threat will be much more expansive, extending north into the Mississippi and Ohio Valleys.
Ahead of an intense area of low pressure aloft sliding through the South in the week ahead, a plume of deep, tropical moisture will be tapped not just from the Gulf of Mexico, but also from the western Caribbean Sea and eastern Pacific Ocean south of southern Mexico's Coast.

This deep moisture is expected to eventually be pulled as far north as Hudson Bay, Canada, over 3,000 miles from its source region, quite anomalous by mid-late November standards. In fact, senior meteorologist Stu Ostro noticed well above-average atmospheric moisture values may extend to the North Pole thanks to this pattern.

By Tuesday or Wednesday, a measure of available moisture in the atmosphere known as precipitable water may reach record November levels in parts of the Great Lakes and Upper Midwest, including parts of Michigan, Wisconsin and Illinois.

Simply put, it will feel quite humid for mid-late November in these areas ahead of the aforementioned storm system.

Upper-Level Pattern, Moisture Setup Wednesday

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