Possible severe weather early Monday, heavy rain expected

(TULSA, Okla.) Showers and thunderstorms are expected to become widespread across eastern Oklahoma and western Arkansas Sunday night as a mid-level shortwave currently spinning over southern Arizona ejects to the northeast. This mid-level feature is expected to be centered over southwest Kansas by sunrise Monday. Meanwhile, the associated surface low is beginning to take shape across southwest Texas. This surface low will track to the north-northeast along a surface boundary that stretches from southwest Texas into northeast Oklahoma tonight into Monday morning. This will allow a warm front to surge to near I-40 by sunrise Monday and drag a cold front through the region late tonight into Monday morning. With that said, abundant deep moisture is expected to surge into the region Sunday night and interact with the aforementioned lifting mechanisms to produce widespread showers and storms across the area into Monday morning. While most of the storms are expected to be elevated in nature, there will be adequate elevated instability and deep layer shear for some of these storms to become strong to severe, with large hail the main concern. There will possibly be a brief window for surface-based storms to develop along the cold front as it moves through the warm sector across southeast Oklahoma overnight. These storms could potentially produce damaging winds and even a brief tornado. In addition to the severe weather potential, locally heavy rainfall will be possible. Most areas will see around one inch of rain into Monday morning. However, some areas across northeast Oklahoma into northwest Arkansas could see upwards of 2.5 inches of rain. This could cause some flooding of low-lying areas. Temperatures into Monday will be rather tricky with warm air surging into portions of the region Sunday night and a possible warm up Monday afternoon as skies clear out. The next chances for precipitation will be late Tuesday night into Wednesday morning as the next mid-level shortwave moves out of the Southwest and across the area. The precipitation is expected to fall as a wintry mix of rain and snow with the greatest potential for accumulating snow across portions of northeast Oklahoma and northwest Arkansas. Current forecast snow accumulations are generally less than an inch. However, there is the potential for greater accumulations across northwest Arkansas. This forecast will continue to be refined as we move closer to the event. At this time, it looks like there could be some travel impacts across northwest Arkansas. High pressure will prevail after the Wednesday system departs through the remainder of the work week. The next chances of rain will arrive Saturday with the approach of the next storm system. Monday A slight chance of showers and thunderstorms before 9am, then a slight chance of showers between 9am and noon. Partly sunny, with a high near 55. East wind 5 to 15 mph becoming west in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 20%. Monday Night Mostly cloudy, then gradually becoming mostly clear, with a low around 29. North wind 5 to 10 mph, with gusts as high as 20 mph. Tuesday Sunny, with a high near 44. Northeast wind around 5 mph. Tuesday Night A 30 percent chance of snow after midnight. Partly cloudy, with a low around 30. Northeast wind around 5 mph. Wednesday A 30 percent chance of snow before noon. Mostly cloudy, with a high near 42. North wind 5 to 10 mph. Wednesday Night Mostly clear, with a low around 25. North wind 5 to 10 mph. Thursday Mostly sunny, with a high near 46. North wind around 5 mph becoming southeast in the afternoon. Thursday Night Partly cloudy, with a low around 32. South wind 5 to 10 mph. Friday Mostly sunny, with a high near 55. South wind 10 to 15 mph, with gusts as high as 25 mph. Friday Night Mostly cloudy, with a low around 45. South wind around 15 mph, with gusts as high as 20 mph. Saturday A 50 percent chance of rain. Mostly cloudy, with a high near 61. South wind 15 to 20 mph, with gusts as high as 25 mph. Saturday Night A 20 percent chance of rain. Partly cloudy, with a low around 38. Southwest wind 5 to 10 mph becoming northwest after midnight. Sunday Sunny, with a high near 56. Northwest wind around 10 mph.