12:15 PM Update
Most of the heavy snow and sleet is off to our NE now as the mid levels dry out. Despite a lack of heavy precip, snow and sleet will still remain across the area this evening with another inch or so of snow and a coating of sleet and possibly a glaze of freezing rain as well. This continued light precip will cause roads to remain slick through the next few hours so continue to use caution if travelling.
Seeing as the storm is winding down, this will be my last update today. I’ll be back tomorrow morning with a look at tomorrow’s weather.
10:30 AM Update
Heavy snow and sleet is ongoing across the region currently although the worst of the worst is now mainly NE of Portland. I expect moderate to heavy snow and sleet to continue for the next few hours with the worst gradually sliding NE. This afternoon, look for the second phase of the storm which is already beginning across southern areas which includes lighter mixed precip.
In Yarmouth, what I’ve been seeing generally seems to match up with other reports I’m seeing on mPING and on Twitter from folks across southern areas. Snow has been heavy here and is mixing with sleet. The sleet is piling up though, I’ve gotten about an inch of sleet on top of 4.5″ of snow as of 10:30. Keep in mind everything is still quite slick out there so use caution if traveling!
7:45 AM Update
Snow continues across the region this morning. Here in Yarmouth, there was a period of sleet around 7 but the precip has since turned back to all snow as heavier precip moved in. As of 7:45, the precip remains all snow with very efficient accumulation. Due to cold temps around the area (10’s for most, 20’s coastal York county), the snow is dry and fluffy. I suggest shoveling/snowblowing now before the sleet turns the snow into frozen cement. Snow and sleet will continue with sleet moving north east through the morning. It seems that a middle of the road solution is playing out across areas north of York County with snow during times of heavy precip and sleet when precip is lighter. This will continue through the morning.
There are reports of many accidents across the are this morning and roads are very slick especially if your area is seeing sleet. Use extra caution on the roads today if you must travel. Also, remember to use your mPING app today! There has already been tons of great data flowing in and it’s really helping with the forecast!
Original 6:15 AM Update
Today will feature a messy winter storm as low pressure moves through the Great Lakes. Warm air will be rising up and over a well-defined cold pool at the surface. This is the lifting that will produce moderate to heavy precip today. I’ve been digging into the depths of the forecast the past few evenings and now it’s time to bring it all together.
Snow is falling across northern parts of New England this morning. Sleet has mixed in as far north as Manchester, NH as well indicating a warm layer already developing aloft. There are two possible solutions with this morning’s snowfall. Our first option is that the sleet line progresses as it has in the past hour unimpeded in its relentless march NE. This would result in sleet arriving during the heaviest of the precip, several hours earlier than last night’s forecast. Should this occur, look for totals lower or just under the lower end of the range from last night’s map (re-posted below). The other idea (this is the one you see above with the HRRR) is that the precip is so heavy that it dynamically cools the atmosphere. This has to do with the displacement of mass and is a topic for another day but the point is that if this occurs, the mid levels of the atmosphere could cool enough to allow for a little more precip to fall as snow thus resulting in totals more towards the middle or even upper end of the total ranges. Be prepared for either of these solutions. Remember even though it accumulates more slowly, sleet is icier and more slippery than snow. It is harder to drive in. Take it slow out there this morning.
Lingering Precip This Afternoon
After the initial burst of snow comes through this morning, precip will shift to a lighter more spotty type. This will fall any number of ways depending on your location. A mix of snow, sleet, and freezing rain is likely across the south with snow and sleet farther north and all snow up in the mountains. The freezing rain expected across the south will continue to cause very slick roads. Slick travel is expected everywhere today but in terms of a complete lack of traction, nothing beats .1-.3″ of ice on top of an inch or two of sleet on top of 4-6″ of snow.
Help Forecasters Track The Storm!
Given the plethora of precip types incoming with this storm, tomorrow would be a great time to give the mPING app a workout! Over the past few days you’ve seen how hard it is to forecast multiple precip types. Here’s a chance for you to help forecasters out! Simply download the free app and take a look outside! Send in your report of snow, sleet, freezing rain, or rain and you can help forecasters like me with forecasting multiple precip type events! The data is sent to the National Severe Storms Laboratory to help with radar development which gives models better data which improves forecasts. Read all about it over on the NSSL webpage. Also through that website, you can view your report and everyone else’s reports to track the rain/snow/sleet line in real-time! This is one of my most valuable tools for tracking the mix line to verify the forecast/make adjustments if needed. Happy reporting!
I keep my map the same this morning as I think each solution (warm or cold) is equally likely. There are interesting radar trends that indicate the colder solution is playing out though you can’t go against hurricane force winds 10,000 feet up blasting in warm air.
We’ll know more as the morning goes on and I’ll keep updating this post as I see changes happening. Keep checking back right here through the morning and I’ll have new info at the top of the page as it comes in. I will also be on twitter with updates all morning @JackSillin.
Here is the link to last night’s post as the information there more or less remains the same.