We’ve been enjoying some Indian summer like weather the last few days, with highs passing the 60 degree mark and skies being mostly sunny. If you’ve been enjoying what we’ve been seeing recently, you’ve got one more day of it coming up tomorrow, before we head into a colder pattern for the end of the week into next weekend and beyond. There’s also a couple of chances for precipitation in the forecast, and we all know what happens when you have cold temps and precipitation J Still a lot of uncertainty as to how the individual events play out, but we’ll go through the models and have a look. Without further ado, here’s the daily discussion.
Models are in good agreement on tomorrow being the warmest day of the period, with highs in the low to mid 60s and mostly cloudy skies expected. We might see some showers from a system that passes well to our north(As shown in the image below from the GGEM model) (If you recall, we discussed this briefly a few discussions ago as a low probability for a snow chance, but likely passing to the north. The likelies won out here), but otherwise, mostly cloudy through the day, perhaps with a brief glimpse of sunshine at times. Chance of precipitation is 50%.
The first of two major deviations in guidance comes late Thursday night into early Friday morning as a wave of overrunning moisture comes in ahead of a weak northern stream wave. The limiting ingredient here that keeps this from becoming a significant event is the lack of low level moisture, which as a result, keeps QPF relatively low. Models are split on how to handle this event, however.
The 12z GGEM is the strongest of the guidance, actually turning the wave into a weak coastal low and as a result bringing the most precipitation to the area of the models. Total QPF is a quarter to a third of an inch, but because of the stronger wave and earlier timing, it would start as rain for all outside of possibly the far NW hills before changing to a mix and finally snow as the low pulls away and colder air filters in overnight. This setup would still produce the most meaningful accumulations of the models, but would at best be a 50/50 split between snow and rain in the interior and mostly rain on the coastline, leading to a coating or so on the shoreline and maybe an inch of snow in the interior early Friday morning. The gallery below shows the GGEM precipitation types at 1 AM Friday morning, the total precipitation as rain, and the total precipitation as snow. Remember that 1 mm = .04 liquid equivalent = ~.4” of snow.
Insofar as a forecast goes, taking a blend of all guidance gives us a chance of some snow showers/ light snow inland on Friday morning with light rain transitioning to light snow/snow showers on the coastline. Looking at guidance, I don’t see any major red flags as to why either camp should be trusted more than the other at the time except for the NAVGEM supporting the wetter camp, so we’ll add a little more weight to that. As a result, we’ll go with a 60/40 blend of the GGEM/GFS combo and the EURO, which gives us a chance of light snow/SHSN inland Friday morning and a chance of light rain transitioning to light snow/snow showers on the coastline. We’ll go with a 60% chance of precipitation for right now considering our blend. As far as accumulations go, the worst case scenario as shown by the GGEM would bring around an inch of snow inland, but it is somewhat of an outlier with that right now, and so we’ll stick closer to the consensus and go with a dusting to a coating on the shoreline, with possibly up to a half an inch or so inland. Keep in mind that we only have 60% chance of precipitation, so it’s still a 4 in 10 shot that we see nothing.
So, to summarize, light snow/rain possible Thursday night into Friday morning, accumulations up to a half an inch possible inland with dusting/coating possible on the coastline, chance of precipitation is 60%.
Behind this event, our first taste of winter cold is expected for Friday, with highs struggling to crack 40 across the state, around 15 degrees below normal, and a solid freeze expected for all Friday night. Skies cloudy in the morning clearing to sunny for the afternoon. Here’s images for the high and low for Friday from the 18z GFS.
The forecast gets more interesting again towards the end of the period. All guidance is in agreement on a wave of energy forming in the gulf late in the weekend and moving up the coastline towards us to start next week, but what path that energy takes and therefore the end result is very different. To show this, the gallery below shows the low placements on the GFS, GGEM and EURO models for 7 AM Monday morning.
Colder weather looks to continue behind this potential event through next week before signs of a relaxation begin to appear in the very long range.
All in all, generally chilly weather expected for the period, with tomorrow being the exception, and two different possibilities for us to see our first flakes lie in the models. As always, questions are welcomed and encouraged, use the comments below or leave us a comment on the FB post. We’ll update again tomorrow evening on Friday mornings event, and potentially issue a snowmap if the odds for snow are still in our favor. Until then though, if you enjoyed the discussion, share it with your friends on Facebook, and have a wonderful rest of your evening!