Happy Saturday! It’s the Saturday before Christmas which means the malls will be packed, Rt 224 will be the 9th Circle of Hell and egg nog will taste extra good by the end of the day. It’s going to a busy and impactful weekend weather-wise so let’s get right to it.
The snow will be largely non-impactful. You may have to brush wet snow off your windshield and decks/patio furniture can get covered but I am not expecting too many issues on paved surfaces as the snow will be falling during the daylight hours into air that is around 32-33 degrees.
Tonight will be quiet with lows in the mid 20s.
CHRISTMAS EVE (DAYLIGHT HOURS)
If you are doing some last-minute traveling or shopping on Sunday, we expect no weather-related issues through the first half of the day. But snow will push back into parts of the Valley during the afternoon. 3pm simulated radar:
At first, the snow won’t be much of a problem on most roads as temperatures will be near or a little above freezing. But after sunset as temperatures drop and the snow becomes more intense, slick conditions will become likely. 9pm:
The snow will continue to fall steadily through about 1-3am, then will taper to flurries/snow showers. A look at the timing of the weather impacts today through Monday morning (clock times at the top of each graphic)
As you can see in the graphic above, the snow will be less problematic by Monday morning and the day as a whole will be cold and quiet with not much more than some morning flurries (“mood snow”!) How much snow will be on the ground Christmas morning? An average of 1-3″ so we are expecting a WHITE CHRISTMAS, officially.
SORRY KOMARA JEWELERS SHOPPERS, WE AREN’T GETTING 4″ ON CHRISTMAS DAY.
THANKS FOR READING! I WISH YOU AND YOURS A MERRY CHRISTMAS!
I’m on vacation this week but I can’t NOT look at the weather! I thought I’d do a quick post with an update on our chances for a “white” Christmas this year.
The snow pack reached a maximum of about 6-7 inches in parts of the Valley a few days ago but it has been receding since, thanks to milder temperatures and a little rain. Animation of the snow cover across the region over the last 2 weeks:
So the chances of the OLD snow still being on the ground come Christmas morning are looking slim. To get a White Christmas, we will need NEW snow. Will we get any?
MOST LIKELY WEATHER DECEMBER 23RD THROUGH 25TH
A cold front will cross the region Friday night into Saturday, bringing rain (and also balmy temperatures ahead of it). Here’s a snapshot of the placement of precipitation Saturday morning, according to the European model:
The key to predicting our weather for the rest of the weekend and into Christmas is: what happens to that front? 1) Does it keep sweeping east and unlock the doors to colder air, or 2) does it stall not far to our east….with waves of moisture coming northward out of the Deep South, keeping the coldest air to the west and making for a wet, not white Christmas Eve and perhaps Christmas Day?
I lean toward idea #2 right now. Why? That’s the solution favored by the “operational” European model and it has decent to good support from it’s “ensembles”, which leads to increased confidence.
Basically the idea is that it’s more likely to rain than snow Sunday night into Christmas morning.
Meanwhile, the US counterpart to the European model, the “GFS”, sweeps the front east over the weekend and the arctic air is allowed to drop anchor across the region. Check out the temperature difference Christmas Day between the European and GFS.
By the way, look at those ridiculously cold temperature over the Upper Midwest. Ouch!
Although the GFS is quite a bit colder, it does NOT bring much hope for a snow “storm” at Christmas. The best we could hope for would be some lake-effect. A couple of the GFS ensemble’s “members” are interesting looking but they are the exception.
Keep in mind we are still a week out and confidence in any forecast (and particularly one involving a wobbly front in the winter) this far out isn’t high. Rely on human forecasters to give you the real story and not national weather apps that are usually based on ONE model.
Christmas 2017 is drawing near and at this time of the year (aside from when we are dealing with snow storms like last night) I am often asked about the chances for a White Christmas. Today is December 14 and Christmas is 11 days away. Which means we are outside of the range where confidence in a forecast is typically high. Particularly in the winter season, and particularly in a challenging climate such as the one we have in northeast Ohio and western PA, I am rarely confident in a forecast beyond 5-7 days.
Looking at a national weather app or web site for a specific Christmas Day forecast this far out?
What we CAN do is look at the overall pattern is likely to be across the country and talk about what the possibilities may be in said pattern.
There is decent model agreement in the overall pattern across the lower 48 states at Christmas: a dip in the jet stream over the Southwest, a ridge of high pressure off the coast of the Southeast and cold air residing near the US-Canadian border and probably in much of the Plains and Rockies as well. The pattern in the upper levels of the atmosphere:
Note how I have “stormy zone” on these maps. There is likely to be a strong temperature “gradient” in place over the country (quite balmy in the Southeast and cold from the Plains west and also in southern Canada). Storms like to reside in between warm and cold air masses. With this type of a setup, it’s likely to be unsettled from the Southwest through the Plains and into the Midwest. This far east? Tougher call. This type of a configuration sometime produces ice storms and mixed precipitation events around the Midwest and Great Lakes.
So I would sum up my thoughts like this:
It will not be super cold here. Very unlikely to be as cold as it is now.
It will not be a bone-dry, sunny period at and around Christmas. Odds favor bouts of precipitation.
What types of precipitation. Timing of any storms. How much snow will be on the ground, if any. In other words, specifics.
Notice we have not picked up an inch or more of snow on December 25th since 2003.
We’ll really be able to start honing in on the Christmas forecast early next week.