Sunday December 11 – A Freezing Rain Advisory has been issued to include central Maryland north of Baltimore between midnight and 7 AM on Monday  December 12. This will be a marginal event, but worth the mention for those traveling in the northern suburbs and across southern Pennsylvania. Will it impact school? That is questionable… But the places to be concerned now include in Maryland: northern Harford, northern Baltimore, Carroll, and Frederick Counties. Also across southern Pennsylvania for Adams, York, and Lancaster.

Temperatures will be near freezing at the surface while warmer air arrives aloft. Computer modeling can have trouble identifying the conditions at the ground. Consider the hills and valleys can vary temperature a few degrees and some cold pocket could remain to have a wet drive turn icy as you turn the corner.
The snow that fell Sunday morning helped to cool down the ground and the air aloft. There was some stickage but the snow had melted shortly after it stopped falling. This sublimation and evaporation chills the ground and holds the cold in a more moist air layer above.  That is one reason I mentioned this morning that I thought the icy conditions would spread farther east than models and NWS were suggesting.

The NAM Model shows the freezing line cutting through northern Harford and Baltimore Counties, Carroll, western Howard, and Frederick Counties in Maryland. This lines up with the Advisory map shown above.

It is likely there will be some icing, but main roads will be thawed and passable for the Monday morning commute. Let’s look at the forecast temperatures overnight. These are at specific locations and does NOT include the colder pockets that are likely in between


Temperatures will be gradually warming during the morning. Typically this early in winter, the influence of elevation and proximity to the warmer Chesapeake Bay makes a difference snow or ice vs just rain. That lines up with I-95 or the foothills to the mountains compared to the flat coastal plain around the Bay.

The Canadian Model was overblown with snow a few days ago. While that was too much, it still has held on to the more icy solution for a few days, and shows it here. This shows more of a wet snow set up, which means colder at cloud level. NWS is suggesting up to 1 inch of snow and a glaze of ice in PA supporting this. Meanwhile the conditions in Maryland will have a more shallow layer of air allowing snowflakes to melt, but cold air at the surface could freeze for a few hours on contact.


NAM Model —>slider

This model does not show the full extent of cold air and ice east of the mountains. But the intensity of the precipitation is why I am sharing this here. Moderate rain likely during Monday morning….

[metaslider id=41159]


See more on the arctic air for the week ahead in this morning’s report.


Faith in the Flakes Online- Flannel PJs Printed Inside Out

Store Now Open

  • We’ve added Flannel PJ Pants that will be printed inside out. They have to be, to make it snow ?
  • Free Personal Delivery for orders of 20 items or more to schools and businesses.
  • Click this image for the online store.
  • Look for more items to be added soon.
  • Also see the info for the STEM Assembly Spirit Wear program:  Put your school name on the shirts and raise money for you PTO/PTA in the process.


thatcher_snowsticksAvailable in 2 Ft, 30 Inches, and 3 Ft Sizes. Also with Orange/Black or Purple/Black. Click on the image to see the options offered by my friend Thatcher at Signs By Tomorrow in Timonium.

Go to to order yours today! Click the ‘Request a Quote’ button at the top of the page. In comment box include color, size and payment information. Please indicate whether you’d like to have us UPS ship them to you or if you would like to pick up in our store. Snow Sticks will ship or will be ready for pick up in our store 48 hrs after order is placed, Mon-Fri.

Please share your thoughts, best weather pics/video, or just keep in touch via social media

Chip KidWxDevicesGet the award winning Kid Weather App I made with my oldest son and support our love for science, weather, and technology. Our 3 year anniversary of the release and our contribution to STEM education is this November. It has been downloaded in 60 countries, and works in both temperature scales. With your support we can expand on the fun introduction to science and real weather.

Also See:

My Winter Outlook for 2016-2017: Colder with snow spread out more

NOAA Winter Outlook for 2016 to 2017

La Nina Formed: What it could mean to our winter

Farmers Almanacs Split On Cold And Snow

Extreme Weather of 2015 balanced out on both ends

Low Snow Winters In Baltimore: Records Might Surprise You

NOAA Ranks Blizzard 2016 4th Worst Snowstorm On Record

Blizzard 2016 Record Top Snowstorm: Area Totals