The US is looking at a very active week of severe weather ahead. Not only will increased atmospheric moisture lead to enhanced instability, it will also up rainfall totals in a big way. With day after day of deluge, parts of Arkansas, Missouri, and Oklahoma have a likely chance at localized flooding.
— NWS Little Rock (@NWSLittleRock) April 25, 2017
Heavy rainfall overnight Tuesday brought rainfall rates of 1-1.5″ per hour. Reports of 2-5″ total came in between Oklahoma City and Tulsa. As this cold front slides east, an enhanced and moderate risk of severe weather will correspond with a bullseye of heavy rain. High resolution computer models have 3-6″ falling in northern Arkansas.
Thursday will bring a break between systems, but a developing surface low and digging mid-level trough out west will slide into the same region Friday. A cold front moving northeast into Friday night will bring a batch of soggy storms. It becomes quasi-stationary allowing rain to continue into Saturday. It won’t be until Sunday that the system finally dislodges and moves out of the lower and mid-Mississippi Valley. Over the next five days, the Weather Prediction Center (NOAA’s branch for high-impact precipitation events and forecast guidance out to 14 days) has a forecast of more than a foot of rain in the region.