Cold fronts tend to be welcome news this time of year, but the one bringing us cooler air for part of this week is coming with a much bigger concern. Our moisture-laden air mass is just poised to bring heavy rainfall. All it needs is a trigger and this cold front and associated upper-level support is just that. Our main issue is that the front will stall out in the area before lifting back to the north. This means a prolonged period of heavy rains for much of the state.
As of Monday afternoon, the cold front was lighting up with heavy and severe storms across central Kansas into Northwestern Oklahoma. The progress southeastward will be slow, but this squall line will be the first of several rounds of heavy rainfall for parts of our area. The first map shows a potential radar solution at midnight tonight. The greatest impact through early Tuesday will be felt from Tulsa to the northwest. The storms will weaken as they slide our way, but the rainfall will remain a concern into Tuesday morning as the heavy cells train over one another. While southeast Oklahoma may stay dry through Tuesday afternoon, parts of northeast Oklahoma could receive a few inches of rain by then. A Flash Flood Watch will be in effect until Wednesday evening along and north of the I-44 corridor.
Widespread showers and storms will once again fire to our west along the stalled out frontal boundary and slide back into our area late Tuesday into Wednesday. While showers are likely during the day Tuesday, the greatest risk of flooding will likely hold off until later that night as the main wave of energy lifts northeast across Green Country then. These slow-moving deluges will provide rainfall rates greater than 1” per hour and quickly cause low-lying roadways to become submerged in water. By midweek, some of our lakes and rivers will also see another rise, most of which remain above normal due to the wet spells over the past 3 months. The corridor that will likely see the most rounds of heavy rain will likely be along I-44. The attached map shows the bullseye of 6” or more of rainfall by late Thursday over central Oklahoma. This is most unwelcome news after Tropical Depression Bill dropped at least that amount of rain in that same area just a few weeks ago.
The silver lining to all of this is the cool-down. Some of our highs may not break 80° Tuesday and/or Wednesday. These 15° below-normal temperatures won’t stick around long, however. As soon as Mother Nature’s faucet switches off, our temperatures will start to soar again. Late in the week, a ridge of high pressure will shove the stormy corridor to our north and bring back the sunshine and heat. As that ridge strengthens, our highs may be back in the mid to upper 90s, with dangerous heat index values well over the century mark by the weekend.
Be aware of the flood threat over the next few days and don’t take a chance with rising waters. Hopefully, the rain will be spaced out enough that flooding won’t be as prevalent, but that could be wishful thinking. In any case, enjoy the break from the heat! Be sure to follow me on Twitter: @GroganontheGO and on my Facebook page for the latest updates on the heavy rains.