Hate it when the data flips.
As I mentioned in yesterday's blog, I was concerned about the data flipping - with regard to the longer range guidance - for the latter part of this weekend into early next week, and was not going to beat the drum too loudly just yet concerning our winter weather potential.
To illustrate this issue, notice the first map, which was based on data initialized Wed morning at 6AM and is valid this coming Tuesday morning at 6AM. The gray/green colors represent modeled precipitation amounts ranging from lightest in the gray to heaviest in the darker shades of green.
The dark blue line usually delineates the rain/snow line with snow more likely on the cold side of that line and rain more likely on the warm side. This solution was also very similar to what the Euro model was showing at the same valid time, so there was good consistency suggesting a significant snow event for much of our state Tuesday.
Now, notice the second map, which was initialized at 6AM this morning and is also valid 6AM this coming Tuesday morning. Obviously, quite a difference as the newer data has shifted nearly all the precipitation much further south, leaving us pretty much high and dry.
In other words, the solution has flipped significantly over the course of the last 24 hours with the newer data base.
The above data is from the GFS model and illustrates the model flips and run to run inconsistencies that we often have to sort out. On the other hand, the Euro model, which is the last map and is valid for noon on Tuesday based on data initialized this morning, is more consistent and continues to show the potential for snow across our state, although it has shifted the heaver amounts further south.
Unfortunately, the problem is that the data may well flip again as the initialization and subsequent solutions are dependent on developments out in the Pacific Ocean and northern Mexico; areas notorious for data voids or data unreliability.
Not shown is that the latest/greatest data now suggests the onset of precipitation will be during the afternoon of Sunday and the modeled vertical temperature profiles strongly suggest ice, primarily in the form of sleet for that event.
At least the morning data runs are pretty consistent from one model to the next in that regard, so have moved up our precipitation chances to Sunday afternoon and overnight and am calling for sleet primarily, although some freezing rain may occur, particularly for the more southern counties.
There may be some lingering wintry precipitation into the day Monday as well. Precipitation amounts will be rather light, but it does not take much ice to create problems.
Also, going with the more consistent Euro solution suggests at least some snow for Tuesday, although given the ongoing uncertainties, the location and amounts will have to await additional data runs.
Between now and then, temperatures will rebound quite nicely for Friday and Saturday with a return to a S/SW wind for much of the day Friday and Saturday along with lots of sunshine.
Daytime highs will be well above normal and should be near 60 Friday and well into the 60s on Saturday.
Then, that next strong cold front will be arriving during the afternoon and evening hours of Saturday followed by much colder conditions for Sunday and into next week as you can see on our forecast page.
So, stay tuned and check back for updates.