Over the past few days modeling has been going back and forth on a phased or unphased storm for Saturday. If the storm is unphased the snow will be more disorganized and lighter across the region, if the storm were to phase then a larger heavier area of snow would occur with a track further north. In terms of accumlations this would make the difference from an inch or so or a storm that would bring more than 4 inches However now there is more confidence now that a less phased solution will occur. Take a look at the 500 mb maps for the recent 12z run and older 00z run for today.
the 12z run is back to being less phased with the storm
the 00z at the same time Saturday morning has already merged/ phased the energy from the southern and northern systems.
with the energy and upward motion needed for low pressure development in two separate regions a more disorganized system is likely. Two areas of precipitation will move from west to east across the region. One more focused from Iowa into the lower Ohio valley Friday night into Christmas day. The other associated with the southern feature moving over the Tennessee valley and deep south. Right now qpf appears to be around or just over .1 from Friday afternoon into Saturday with the steadiest snow falling late Friday night and Saturday morning. This will likely create some travel issued around the region and i expect a winter weather advisory to be issued sometime Friday. Behind the system the wind off the great lakes is favorable for additional snow showers through Sunday with more light accumulations. This brings storm totals to 1-3 inches by Sunday afternoon. Let’s take a look at our storm a very good track but unphased and disorganized. If the storm was more phased a snowfall over 4 inches would have occurred, this outcome looks highly unlikely. there is also an outside chance precipitation starts as rain but all snow is expected at this time.
GFS
Christmas eve
christmas morning
Sunday night
NAM
Christmas eve
christmas morning
sunday afternoon
highs will be in the mid 30’s Friday. Light snow is expected for Friday night Through Saturday with snow showers into Sunday. lows will be in the 20’s Christmas morning with highs near 30 Saturday. Temperature Sunday will be in the 20’s with the snow showers.
For an offical white christmas an inch of snow needs to be on the ground sometime christmas day. Right now the odds are very good off seeing an inch of snow christmas day but with thie disorginzed nature of the storm there is a chance Bowlign green sees one badn of light snow and one to the south. my white-o-meter indicates a white chirstmas as snow falling anytime during the day or any accumlation on the ground. The offical defintion is more strict.
white-o-meter: 9.99/10 ( don’t want a jinx)
chance of official white Christmas 9/10
happy holidays to all!!!! No more updates will be issued on this storm unless there is a signficant change in forecast thinking.
12 euro trended wetter showing .25-.5 qpf for the region. this is a total reversal of where the models were yesturday in terms of driest to wettest. this would imply a bump up in snow totals. Will wait till after 00z US models come in before deciding upon this since the qpf range is large still in the modeling.