One more mild and relatively warm day is expected with highs in the mid 50s across most of the area. A weak front will slide across the area today and colder air will filter in behind this boundary later tonight. Gusty north winds will crate a wind chill this afternoon. A mix of sun and clouds will be likely.
The first system, currently nearing the southern California coastline, will move eastward soon. Rain will be likely across Texas Saturday evening and Sunday morning and some showers or snow will be likely across extreme southern OK by early Sunday morning. This will more than likely stay too far south to have a major impact on the Tulsa metro but it's not impossible to see some light snow showers Sunday because of the proximity of this system.
The higher likelihood for snow with this southern system will be across the southern third of the state and mainly extreme southeastern OK where 1 to 3 inches of wet snow may be possible.
An upper level jet streak may provide enough lift combined with moisture to produce some light snow Sunday afternoon or evening into the northern part of the state. This would not be significant, but some is a possibility.
Our main player will be arriving Monday in the form of an upper level system dropping rapidly down the northern high plains into the central plains states. Snow will be possible Monday across northern and central OK including accumulating snowfall with highs near freezing. The timing and amount of the system is yet to be known with any confidence, but more than likely a 1 to 3 inch snowfall is possible with most of the action arriving in NE OK by Monday afternoon. This morning's model data seemed to hint at keeping most of this system to the north of our immediate area, but we'll stay the course with for this forecast cycle with a decent chance of measurable snow Monday.
The cold arctic air will slide southward and overtake a large portion of the nation for most of the week. EURO and GFS data indicate warmer air will arrive Thursday or Friday in the form of upper 30s but I question this solution. Once a shallow arctic air mass is in place, it's usually eroded too quickly by model data and ends up staying an extra day or so. Plus, if we do get the measurable snowfall across the northern OK area Monday, this will act to keep the temps even colder for a longer period. I expect most of next week to be at our below freezing for the period through Thursday with some above freezing temperatures by Friday.
Extended model data suggest the pattern will remain favorable for another surge of cold arctic air to arrive late next weekend. Welcome to January.