Hope you have enjoyed the relatively warm weather over the last few days. In fact, we were just a few degrees short of setting a record for warmest overnight low for this date as we only dropped to 53 degrees this morning. Strong southerly winds, overcast skies, and low-mid 60s have been the general rule this afternoon. That is all about to change as a strong cold front will be arriving around sunrise Friday morning which will be followed by much colder temperatures and then a chance of precipitation. The precipitation type is where it gets interesting along with the amounts as this looks to be a very wet system.
Speaking of precipitation amounts, notice the QPF map on the right through this weekend. This system will be capable of dropping several inches of rain with widespread showers and embedded thunderstorms starting later Friday night and continuing through the day Saturday. As the rain comes to an end Saturday night, there remains the possibility of a transition to snow along and N of I-44 and 1-2" may occur up to the KS state line. That will be ending early on Sunday followed by clearing skies that afternoon.
I have used an inverted temperature profile for Friday since the timing of the cold front has been delayed somewhat. It now appears it will be moving through the I-44 corridor shortly before sunrise and temperatures will be in the 50s and 60s ahead of the front along with cloudy skies and gusty southerly winds. Behind the cold front, winds will shift to northerly and temperatures will be falling. Here in Tulsa, we will be in the low-mid 30s by the Noon hour and not likely warming much for the rest of the day. With the possible exception of some drizzle or a light mist, Friday will be for the most part dry. However, with temperatures below freezing for the more NW counties, there could be a light glaze form on elevated surfaces.
The main event still looks to be later Friday night through the day Saturday when a disturbance aloft will be moving over the state. This will bring warm, moist air over the top of the shallow, cold air near the surface. Again, temperatures may be cold enough for a period of freezing rain NW of I-44 during the Friday night time frame. As we go on into the day Saturday, temperatures should climb above freezing area-wide, but the rain will be widespread with several inches possible and the potential for some flooding issues, mainly for the more SE counties.
As the upper level storm system moves on eastward, colder air at the surface and aloft will fill in behind it providing an opportunity for the rain to change over to snow, mainly along the OK/KS state line where an inch or two will be possible. Heavier amounts on into KS may cause some travel difficulties for Sunday.
Temperatures will likely stay in the 30s for daytime highs through the weekend and early next week. Christmas Eve and Christmas Day should make it into the 40s. Another, weaker system now looks to be moving quickly across the state late Christmas Day or that night and could produce some flurries before ending Thursday morning.
All in all, a return to much below normal temperatures through this forecast cycle along with a very wet period centered basically around Saturday. So, stay tuned and check back for updates.