Most of won’t see much in the way of snowfall this morning, but temperatures are close to freezing so what falls may cause minor problems. Snow, sleet, freezing rain or just rain should develop between 8 and 9AM, continue through the morning and then end by or just after noon. Then we warm up for a couple of days.

Sunday, February 21, 10:30AM

We have a decent warm up coming mid week but before then we have one more event to get through. Precipitation is expected to arrive from west to east tomorrow morning beginning around 9AM. Once again, temperatures aloft will be marginal so northern areas will have the most impact but it is looking right now like all of central MD will see some snow in the morning. In the areas that stay all snow, it may be moderate to possibly heavy snow for several hours. By noon or early afternoon, most areas will see improving conditions as temperatures rise above freezing and precip transitions to rain ending by 2 or 3PM.

I’ll update later this evening or early Monday morning.

Thursday, February 18, 7AM

I briefly mentioned in the last update that if the snow changed to sleet faster than expected then snow totals would be significantly reduced, but for most of us, 3 – 6″ of snow has become 3 to 6 flakes. A pesky warm layer is just above the surface and that caused most of us to start as sleet, though I’ve read reports near Frederick of several inches of snow. Unfortunately, if you don’t have snow now, that likely means that you are going to be dealing with sleet and freezing rain for most of the day. I did not expect any freezing rain this morning which may not bode well for the remainder of the day. I’d much rather have sleet because sleet can’t accumulate on power lines. Freezing rain sucks. Regardless, surface temperatures will likely stay well below freezing today so avoid travel if possible.

It looks like there will be a lull in precipitation well afternoon, but another round of precip is possible tomorrow. I’ll try to get that one right in a later update.

Wednesday, February 17, 11AM

Winter Storm Warnings are up pretty much the entire region for snow that begins before dawn tomorrow morning, becomes heavy in most areas after sunrise, and then may or may not change to sleet. Cold arctic air is in place, so it’s a pretty good bet that all of central MD will see all frozen precipitation throughout the day tomorrow. Surface temperatures will likely stay below freezing on northeasterly winds, and the only question now is how much warm air flows into the mid levels causing snow to change to sleet. For areas along and east of 95 that changeover is inevitable, and there could be a prolonged period of heavy sleet on top of any snow that falls. For the normally colder western and northern areas, the changeover comes later in the day or not at all. In either case, roads tomorrow will be very icy. Tomorrow will be a good day to watch the snow and sleet fall and do nothing about it. I wouldn’t recommend shoveling this mess until everything has fallen because the snow will make for a nice base for the concrete that will be falling on top of it.

Right now expect 2 – 4″ of snow and sleet to the south and east of 95, and 3 – 6″ west and north, with higher amounts possible west of route 15 and along the MD/PA line. Those amounts would be reduced significantly if the sleet change happens quicker than anticipated, but right now I think we all see a decent period of heavy snow.

I’ll update later this evening with any changes.

Tuesday, February 16, 3PM

The models continue to converge on a Winter Storm Warning event for areas north and west of I-95 in central MD beginning before sunrise Thursday and continuing through the day. All midday models either held serve or got colder than previous runs so I expect the NWS will issue Winter Storm Watches this afternoon for most of the region. It still looks like most of us start as snow and then possibly change over to sleet and or freezing rain later in the morning or early afternoon. Those details can be sorted out as we get closer to the event, but one thing that is looking better than any storm we’ve had so far this winter is that cold air will be available for the duration of the storm. Strong high pressure is expected to be anchored over New England on Thursday, so unless that changes, northeasterly winds will force cold air down the coast, and whatever falls on Thursday will eventually be frozen. For those that want all snow, we need to see some more changes in the warm air advection being advertised by the NAM models to keep all levels cold enough to support snow. The GFS has been trending in the the right direction, and the Euro this afternoon went all snow for most areas west of 95, but it’s hard to bet against the NAM as it has been the model that seems to have done the best this year. It still says snow to sleet (and maybe a lot) to freezing rain with below freezing surface temperatures, but it has the least amount of snow. Either way, Thursday travel looks to be difficult.

I’ll update again tomorrow.

Monday, February 15, 10PM

Just a heads up, but Thursday is going to be a mess. All models suggest heavy AM snow to sleet and freezing rain, but every model has been trending colder so I’ll update periodically this week.

Saturday, February 13, 10AM

Precipitation is breaking out across the area, especially south of I 70, and anything that falls today will eventually be frozen as temperatures and dew points are well below freezing. The areas south and east of 95 have the potential to see the highest precipitation totals, but most accidents in freezing rain events occur just as the precipitation starts regardless of how heavy so be careful today and tonight.

Temperatures should climb above freezing Sunday morning, but until then, much of the area will be glazed over in a thin sheet of ice.

Fortunately, models have trended drier and south with tomorrow’s potential ice storm. Right now it looks like PG, Calvert, and St. Mary’s counties are the unlucky winners of a significant icing event, but even there, expected precipitation totals are much diminished compared to model runs a couple of days ago. A word of caution, however, because just about every storm this winter has had some significant changes in the forecast in the 24 hours before onset, so central MD could still be impacted.

As of now, light sleet and freezing rain should spread into the southern counties mentioned above during the morning hours tomorrow. Keep in mind that light freezing rain is generally the worst when temperatures are not super-cold, like now, because it has the highest accretion rates (accumulation), so any freezing rain should be taken seriously. For central MD, patchy light freezing rain or drizzle is possible during the afternoon and throughout Saturday night into early Sunday morning so know that icy conditions may be present throughout the region until temperatures climb above freezing midday Sunday.

I’ll update again tomorrow morning with any changes.

Thursday, February 11, 7AM

The second low pressure ripple along the boundary will slide to our south later today, so although we may see some light mixed precipitation in some areas, we should have a little break before the next storm on Saturday. Right now that looks to begin in the early afternoon as a mix and unfortunately could turn in to a sizeable freezing rain event. As of now, temperatures are modeled to be well below freezing for the duration of the storm for all of central MD but with warm air aloft, the predominant type of precipitation would be sleet and freezing rain. That’s still a couple days away and one thing that the models have not done well with this winter is with temperatures. Modeled temperatures have been somewhat colder than what has actually happened, so it’s still possible for changes to the forecast.

I’ll update either later today or tomorrow as that could be a high impact event. Looking ahead, the train of winter storms looks to continue next week as early as Tuesday.

Tonight’s wave of low pressure is intensifying a bit more than first thought and as a result, we may end up on the high end of the 2 – 4″ mentioned this morning. There’s a pretty sharp cutoff between snow and slop, and right around the ICC is still a good guess. Accumulations will vary from about 1 – 2″ south of the ICC, 2 – 4″ north of there to about I-70, and 3 – 5″ north of there to the PA line. Western areas and the Parr’s Ridge crew in Carroll county could do a little better than that and Winter Storm Warnings have been issued in those areas. The rest of us are currently under the lesser Winter Weather Advisory. Some light snow is already starting to develop in western areas but I don’t think the accumulating rates will come until after 7 this evening. Snow continues overnight and ends just after sunrise tomorrow.

The second batch of precipitation that was mentioned this morning looks to stay well south of us tomorrow night, but Saturday afternoon and night has the potential to be very icy with temperatures below freezing with sleet and freezing rain. I’ll update that tomorrow.