It’s the “buzz” today…the potential storm on Monday. If you frequent the computer model websites, then you have certainly noticed the inconsistent model solutions regarding the Monday/Tuesday time period. This is not surprising, since we are looking 5-6 days out. It’s easy to get frustrated, but take my word for it–don’t waste that extra second you get today on that.
I can point out forecasts that show OKC getting the following: nothing at all, mixed precipitation, flurries, and over six inches of snow (no–that’ s not the official forecast–that’s how rumors get started!) When the models get this funky, you need to go beyond what the precipitation output map says, and look at the bigger picture. We know that there’s a storm system that will move out toward a cold airmass. We will watch for the differences in both features–the cold air and the upper storm to see exactly how this sets up.
Here are the factors to watch over the next few days….
1) Temperatures: The cold air is up there and it’s going to move in. What we will need to watch is the depth of the cold air. For a heavy snow event, we need the entire column to be at or below freezing. Our best snows occur with temperatures from the mid 20s to the low 30s. Generally, when it gets very cold around here, it also gets very dry.
Based on what I’m seeing right now, we should have the cold air in place. It will get more shallow as we get into southcentral/southeastern Oklahoma.
2) Moisture: A lot of storms look good a few days out, then we get too dry in the lower levels of the atmosphere. We’re not just talking about the surface, but from 10,000 feet and below. Today’s 12z GFS does just that–shoves all moisture/moisture transport into Texas, keeping us dry. Earlier runs had better moisture for us. Based on what I have seen today, and the past few days, I still like a a 40% (pop) for Monday, and a 30% for Tuesday. Higher chances exist for southern Oklahoma, lower for northern Oklahoma.
3) Track, speed and intensity of the upper storm. Again–model forecasts vary from swinging out of the southwest directly over Oklahoma, and passing well to our south over central/southern Texas. The closer it is, the higher the impact. A faster storm limits the window for precipitation. A strong storm increases the lift.
Based on everything that I’ve seen so far, here’s my current call:
Northwest Oklahoma: coldest air, most likely area for all snow, but also has least available moisture, so would overall has the lowest chance for precipitation
Southwest/central/northeastern Oklahoma: could see the perfect combination of all of the above–and needs to watch the above factors carefully. Even though the 12z computer models (minus the European that isn’t here yet) don’t show it, the trends are there to support an accumulating snow in this area Monday-early Tuesday.
Southeastern Oklahoma: appears to be mainly rain. If that storm track is further south *and* the cold air is deep enough, then southeastern Oklahoma could get hit hard by snow. This area could also see some sleet.
Bottom line–it’s still five to six days way. It will change. It certainly has our attention. Give this thing another day or two on the models–enjoy your New Year’s and we’ll talk more about it over the next few days…