No one ever said forecasting the weather was easy. Starting Sunday it gets even harder than normal for us forecasting the weather in the eastern half of the country. The problem is a cut-off low that develops Sunday.
These types of lows because they are cut-off from the main steering currents in the atmosphere become extremely difficult to forecast. Mainly because until they actually cut-off you don’t know exactly where this will happen. Then because they are out of the main steering flow the movement of them is hard to gauge. Then with this one you throw in cold air aloft and now snow/rain/sleet are thrown into the mix. (No pun intended ) Which makes me want to pull out what little hair I have left on my head.
Here’s what I know right now based on the available data at this time.
ECMWF or Euro model Tuesday:
Notice that 540 line (blue dashed line) over the piedmont of NC? That is the rain/snow line and notice there is moisture there which could mean snow mixed with rain Tuesday night, even in Charlotte.
GFS Model same time as above:
The position of the upper low is the same, but the GFS is colder and drier over the piedmont. Looks plenty cold enough for a few flakes but we get dry slotted so likely nothing.
GEM or Canadian model same time frame:
This model has an upper low much further south and east which puts us in very heavy rain.
HPC snowfall outlook:
As you can see I’m not the only one struggling with this. HPC or NOAA has a huge area of possible 1” snow but the chances are only 10-20%. Basically this means uncertainty…big time!
Too early to know but the same GFS model mentioned above plots this.Take it with a extremely large grain of salt.
Stay tuned this could be very interesting and very frustrating. There is extreme uncertainty in the forecast right now, but once the low cuts-off we will have a much better idea. That will likely happen Sunday.