October will be very active for the eastern part of the country. We will experience the first system starting tomorrow, for parts of Oklahoma. A very strong cold front is diving south across the northern United States, ushering in unseasonably cold air and snow to that part of the county. You can see the chilly air pushing south.
This cold front will continue moving south, and will push through Oklahoma tomorrow, followed by Texas on on Friday. Behind the front, winds will be strong out of the north around 20 to 30 mph which will send temperatures tumbling. Saturday will be the coldest day thus far, this season. Temperatures will stay in the 50's across north Texas and in the 40's across Oklahoma & Kansas; a 39 degree reading in parts of Oklahoma and/or Kansas is possible. Saturday will shatter several record low maximum high temperatures for several cities including OKC (55) and Tulsa (57). This map shows how cool the NAM is keeping our area on Saturday.
A line of showers & weak thunderstorms will accompany the front as it treks through the Southern Plains on Thursday and Friday. Post frontal rain chances will increase on Friday through Saturday as a weak wave rounds the base of the trough. The majority of the rain should stay in Kansas and Oklahoma, but there's a chance for showers across northern Texas. The rain should remain light to moderate, but none the less it'll be a good soaking rain; amounts on the order of .1-.4".
Some of the guidance has been 'hinting' at wintry precipitation for parts of Kansas and northern Oklahoma. While this is very early in the season, it's not impossible. The soundings for northern Oklahoma and southern Kansas do not appear to be conducive for snow, at this point; however, there are times that we don't have reliable soundings until several hours before an event. With that said, I do not believe that it's entirely impossible for wet flakes to mix in with the rain briefly on Saturday across southern Kansas and northern Oklahoma. I'll continue to closely evaluate this and bring updates as needed.
One of the bigger concerns will be the potential for a frost or freeze for parts of the Southern Plains. The best night for radiative cooling will be Saturday night. Wherever the skies clear, expect near freezing conditions. The areas that need to prepare are: Kansas, central and northern Oklahoma, the Panhandles of Texas and Oklahoma, Missouri, and northern Arkansas. Temperatures in these areas will range from 30-38 degrees on Sunday morning. Make sure you watch out for you "Three P's"-pets, plants, and pipes. The areas that are included in the blue shaded box are the areas that will likely see a frost-across the southern portions, and a freeze across the northern sections.
The rest of October looks active too. Several storm systems will impact the Southern Plains as well as the eastern seaboard. Cold shots will continue to dive south, so it'll be interesting to see if the northern branch can interact with the southern branch in October. The next storm system to impact the Southern Plains will be around Thursday of next week.