Flooding Rainfall Coming to Green Country

The major storm system we've been tracking from the Pacific Ocean to the Plains is finally upon us, and is looking as ominous as ever. For the past week, the moisture content in the atmosphere has been building with a continuous warm, moist flow from the Gulf of Mexico. The combination of moisture and a strong, slow storm system spells trouble for the week ahead.

The initial threat will be severe thunderstorms on Monday. Storms will continue to develop along and ahead of a dry line, which will be merging with a cold front during the day, Monday. The computer models differ on the timing, but starting late Monday morning some heavy-duty storms along a previously-formed band of heavy rain will likely push into eastern Oklahoma. Instability with strong wind shear will allow for severe storms with supercellular characteristics to form. High winds and large hail are the main threats, but tornadoes will be possible as well – especially in southeastern Oklahoma.

The threat then shifts to flooding. The cold front will essentially stall out near the Oklahoma/Arkansas border as the upper-level becomes cut-off to our west. That set-up will allow several waves of very heavy rain and embedded thunderstorms to train over the stalled front (from south to north), which will waver east and west in our area. This is a very tough scenario to nail down the maximum areas of rainfall, but the bulls-eye will likely lie in eastern Oklahoma as the 5-Day rain total map from the Hydrometeorological Prediction Center shows above. Any shift in that meandering upper-level low could mean drastically lower (or higher) rain totals for us. One thing we are fairly confident about is that somewhere is going to get a very dangerous amount of water. Locally a FOOT of rain could fall through midweek.

This will likely be a major, if not catastrophic flooding event if this system's evolution pans out like it has been modeled over the past several days. Since it is Spring Break for Oklahoma students, many families are out camping or enjoying recreational activities outdoors. My recommendation is that you postpone any activity that involves being near rivers or streams through midweek. River and stream flooding is anticipated along with flash flooding all throughout Green Country. This could be a life-threatening situation for anyone who ignores the flooding threat this week.

This stubborn upper-level low will finally drift east by the end of the week, leaving us with some time to dry out. Until then, stay weather-aware and plan indoor activities. Monday and Tuesday, at the very least, will probably be a washout. We'll keep you up to date with the latest here at Newson6 as the various threats unfold. I'll have frequent updates on the storm on Twitter: @GroganontheGO and on my Facebook page. Be sure to follow me there if you don't already!