TULSA, Oklahoma - For the last few days, have spent some time discussing the long range model guidance in the days leading up to Christmas and pointing out those longer time ranges can be very misleading. For example, the first map shows the GFS solution valid Dec 23 at 6 PM from data initialized at 6 AM this past Tuesday. That particular solution, if it verified, would produce significant amounts of snow for that evening and overnight and quite likely would leave us with a White Christmas.

The second map is the GFS solution also valid Dec 23 at 6 PM but from data initialized at 6 AM yesterday morning. Notice that solution does not suggest any wintry weather for us and therefore no chance for a White Christmas.

Now, notice the third map which is the GFS solution also valid Dec 23 at 6 PM but from data initialized at 6AM this morning. Notice that solution is a far cry from the first map and just goes to show how dependent a particular solution is on the initialization and why we take those longer range products with a grain of salt. If the second and third maps would have been more consistent with what the first map was showing, then we would at least have had some confidence in a significant snowstorm leading up to Christmas. In other words, if there had been some run to run consistency in the solutions, then we would be beating the drums regarding the possibility of a White Christmas. Of course, there is still time for those solutions to flip-flop again, but for now that possibility looks to be very unlikely.

Another factor is that the time range we are talking about is still beyond the time domain of the other long range guidance such as the ECMWF so there is no other solution to compare with. Obviously, in the days ahead we will have more run to run comparisons and model to model comparisons as we get into the 240 hour time domain of the ECMWF so we will see how that shakes out in the days ahead.

In the meantime, we were fortunate to see some brief breaks in the clouds this afternoon but a low level cloud deck will prevail for later tonight through the day Friday and into the day Saturday. We may see a few breaks in the clouds Saturday PM and again Sun PM but really not expecting to see much in the way of sunshine till early next week.

Along with the clouds comes a chance of mist, or drizzle, or a few light showers by Friday morning and into the day Saturday. Fog is also a possibility, particularly during the morning hours of Fri/Sat. A stronger storm system aloft will be moving across the state later Sunday and that system will bring with it more widespread showers and the potential for some thunder. That will be ending by early Monday morning followed by some sunshine for early next week. This could be a rather wet system as well; notice the 7 day QPF map for example which has the potential for up to an inch or more for some locations.

Temperatures in the meantime will be much warmer than normal, particularly at night. Morning lows will be in the 40s again tonight and likely in the 50s for Sat/Sun mornings. Keep in mind our normal daytime highs are only around 50 at this time of year. Speaking of daytime temperatures, mid 50s are expected for Friday due to the clouds and drizzle, but 60s for Saturday and Sunday due to stronger southerly winds and at least a few rays of sunshine.

Early next week will be dry and more seasonal with respect to temperatures along with brisk northerly winds. However, there are indications of another very wet system headed our way late next week and perhaps into the early part of that weekend. That system is not being handled very consistently by the longer range guidance either, so will hold off on making any forecasts regarding the precipitation type at this time.

Notice though the last two maps which have the 8-14 day guidance which does take us up to Christmas Day. As you can see, that particular product still suggests temperatures will average above normal during that week long period along with some precipitation potential, most of which will likely be as mentioned above late next week or the early part of that weekend before Christmas.

So, stay tuned and check back for updates.

Dick Faurot