A significant winter storm still looks likely to strike the Mid-Atlantic on Wednesday. Winter weather conditions will over spread the area early tomorrow morning before transitioning to a period of ice then rain in the afternoon. Some details have come into better focus since yesterday. locally, I am still expecting a moderate impact that will likely close schools and cause travel difficulties. The National Weather Service has now issued a Winter Storm WARNING for a large chunk of the Mid-Atlantic from I-95 to the north and west. This is where the highest snow totals will be and where ice totals will have the highest impact. Across the coastal plain, including Southern MD, it's a Winter Weather ADVISORY. Snow and ice totals will not be as high here, but winter weather is still expected. Snow still looks likely to move into the region between 5 and 8 in the morning. A change to this part of the forecast is that it looks like coastal areas in Southern St. Mary's and Calvert (locations closest to the opening of the Bay) may be a touch warmer. This could lead to localized areas of sleet or freezing rain developing there first. You can see that develop throughout the morning on the Futurecast below. Light to moderate snow continues until we hit the lunch hour; that is when the regional changeover to sleet and freezing rain will start. The most recent model runs have shown a dry slot potentially developing over area south of Route 231 by midday, as shown below. If this happens, snow and ice totals will likely be kept down. If you remember back to the January storm, many saw that dry slot happen, lowering their backyard totals just a bit. It looks like the heaviest snows will indeed stay north and west of DC. It is also there that ice may hang on the longest. This model's automated snow output very much agree's with my forecast. I do agree the idea that the heaviest snows may be kept to the north and west, away from Southern Maryland. Areas northwest of I-95 likely see over 4" of snow from this storm. Along I-95, including PG and Anne Arundel Counties, 3-5" looks likely there. Across Southern Maryland a general 2-4" looks likely, especially for those north of Route 231. South of that point across southern Calvert and St. Mary's County 1-2" is likely there. Our local forecast is very dependent on that dry slot. If it does indeed occur, then your backyard totals will likely be on the lower side. If that dry slot does not happen and heavier snows work in, then totals will be on the higher side. The same general rule of higher totals north and west of I-95 will hold true for the ice as well. High impacts from ice, totaling over 1/4" of an inch, looks likely in the MD/WV panhandles and across the Shenandoah Valley. From there to I-95 a moderate impact from ice totaling from 1/10" to 1/4" seems likely. It is in these two zones that Ice is almost certain for some period of time. From I-95 to the southeast to Route 231 an elevated impact from a glaze of ice will be possible. Coastal locations may be spared from ice due to that dry slot. A moderate to significant impact winter storm still looks very likely for the Mid-Atlantic. I expect widespread school closings and travel difficulties. The biggest change from yesterday is that it looks like a developing dry slot may spare Southern MD from significant ice and snow. Regardless, moderate impacts are still likely though mid-afternoon. I will continue to provide updates throughout the day tomorrow to keep you ahead of the storm. Follow me on Facebook or Twitter for Southern MD weather updates!
Lead Forecaster -John A. Bordash
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A high impact winter storm is likely to impact the region on Wednesday. Yes, schools and travel are likely to see significant impacts . This is all due to a storm that will move to our west, overspreading precipitation across the Mid-Atlantic late Tuesday into Wednesday. You may be thinking to yourself, "The biggest Mid-Atlantic snows occur normally when a storm slides to our south or off the coast to the east. How is this storm to our west going to give us winter weather?" An area of high pressure to our north will help to channel in cold air Tuesday and Wednesday. It will be because of that cold high to the north that will allow the precipitation that falls to be a wintry mix. The National Weather Service has gone ahead and issued a Winter Storm WATCH for many in the Mid-Atlantic. As you can see below, locally this does include the colder areas of Anne Arundel, Charles, and Prince George's Counties. Others outside of the Watch (like Calvert, St. Mary's, and Westmoreland) will also see snow. However, it likely will not be the magnitude the northwestern zones will see. These types of set ups typically favor communities to the north and west of I-95. Because these zones are normally colder it is hear that sees the most snow and ice. However, that area of high pressure, that's pumping in the cold air, is very strong. That will lead to everyone initially starting as snow Wednesday morning. The snow could be heavy at times. Some computer model data shows areas south of DC seeing an enhancement in snowfall totals because of the heavy snow. I'm not sold on that solution yet, but it is a solution that is on the table. As you see in the timeline below, by mid-morning everyone should be seeing snow. As warm air from the south works in, the change over to sleet and freezing rain will occur around midday. This is likely to create an icy mess, especially north and west of I-95. The warm air will continue to work north, eventually turning everyone over to rain. Again, a period of snow is likely for everyone. From Ridge, to Huntingtown, to La Plata, and Annapolis most should see a period of snow in the morning. How long that period will last is uncertain. However, I would think we should see a good 3-6 hours of snow. Right now it looks like the highest totals will be northwest of I-95, where snow lasts the longest. As mentioned before, some models have consistently shown some enhancement to snow totals across areas south of DC. This is before these models show the snow hanging on longer, and showing that snow as very heavy snow. Some of your weather apps may be showing higher snow totals for Southern MD than I have shown, and that's why. I wouldn't hold my breath for that solution, but it is something to keep in the back of your head. Shown below is my first call on snowfall. As mentioned before, many are likely to see a period of ice between the switch over from snow to rain. This transition period when the ice falls is likely to last the longest out west; where it is coldest. Western zones could see a high impact from ice, totaling over a quarter inch. Just to the northwest of I-95 moderate impacts are likely, with ice there totaling from a tenth to a quarter inch. Along I-95 and to the slight southeast, a glaze of ice could lead to some elevated impacts. Locations along the coastal plain are not likely to see an over abundance of ice. This is because those communities sit near, or right at sea level. The "warm" water temps above freezing should make the transition quicker for those areas. Elevated: Glaze - .1" of ice Moderate: .1" - .25" of ice High: Over .25" of ice A high impact winter storm is likely to bring snow, ice, and rain the entire Mid-Atlantic. While areas north and west of I-95 are likely to see the highest totals of snow and ice, everyone should see wintry weather Wednesday morning. I do believe that many schools are likely to close on Wednesday and travel will be significantly impacted. This is a low confidence forecast. If temperatures warm quicker than expected, or a dry slot develops, totals could be lower. On the other hand, if the cold air stays longer or there are heavier snow bands, totals could be significantly higher. There's a lot to watch over the next 36 hours leading up to this storm. Prepare now, and follow JB Weather on Facebook and Twitter for the latest updates.
Lead Forecaster -John A. Bordash Snow still looks likely for Saturday across the Southern Mid-Atlantic. A weak area of low pressure will move to our south, overspreading moisture across the forecast region. The precipitation will be met with cool temperatures in the 30s. This set up should allow for an initial burst of rain to switch over to some light snow by midday/early afternoon on Saturday. This never has, and still does not look like a blockbuster snowstorm for our area. This should really only be a minimal event at best. As things stand right now, it looks like precipitation should move into the region during the early-to-mid morning hours. Starting as rain, we should see a transition to snow by lunch time. Relying on this transition to occur does make me nervous. There have been plenty of times where a set up like this has not produced snow, and leads to a busted forecast. This is why this forecast is a low confidence one. Shown below is the in-house Futurecast. It shows that timeline of rain going to snow by the afternoon well. Again, not looking at heavy snow, just a light but sustained light snow. Shown at the end is forecasted amounts from the American Model. While this is not my forecast, it does should that the higher snow totals will be south of DC. This should be a low impact event for many; especially since this a Saturday event. Nevertheless, this could make roadways a tad slick. With the warm temperatures on Friday, and above freezing temps on Saturday, not too much should stick to major roadways. Most accumulation should be on grassy areas. Considering this storm is weak, that means there is a higher degree of variability with the forecast. These smaller system are notorious for making last minute track and atmospheric changes. A move just 30 miles to the north could tack on another inch or two to the forecast, and bring in heavier snow. On the other hand, if this system tracks 30 miles to the south, Southern MD will not see much at all. Both of these options are very much on the table. As things stand now, a nice 1-3" of wet snow look to fall on Saturday across the region. This low impact event will have marginal temperatures to contend with, which could lead to lower snow totals. Stay with JB Weather for the latest updates on this changing forecast. Lead Forecaster
-John A. Bordash The middle of February id looming, which is Southern MD's climatological snow peak. Accordingly so, our winter storm threats look to be increasing. Right now, I am monitoring three potential threats over the next 7-10 days. The first winter storm threat looks to be during the day on Saturday. This does not appear to be any sort of crippling, record setting blizzard. However, it does look like a decent shot of some accumulating snow. Initially, we will have a brief warm up on Thursday and Friday. An area of high pressure off the coastline will help to pump in some warm temperatures. Highs the next two days are likely to be the upper 50s to near 60! The cold front will move through Friday afternoon. There could be a few rain showers associated with it, but that is it. The cold front will stall out just to our south, ushering in the cold air; and essentially being used as train tracks to guide the Saturday system. The cold air that will move into the region this weekend will not be, "Polar Vortex," like cold air. It will bring temps down to the lower 30s, but that is all we need for snow. Coming off such warm temperatures the day before, it looks like any precip that falls will initially start as rain and then transition to snow. Generally speaking, I am not expecting amazingly high snowfall totals with this storm. Shown below are my thoughts, and it looks like a nuisance sized-event is likely. However, because the system is weak, there is a higher degree of uncertainty. If the storm is slowed down a touch, or is further south, that could bode well for snow lovers. My First Call map will be out tomorrow! Looking ahead, our next two winter threats are on Sunday and then again on Tuesday/Wednesday. Below I show my initial thoughts for each.
There is a lot to watch over the next 7-10 days. In its last month, winter may finally be trying to get itself together. Our first and most concrete threat comes Saturday. Even though we still have some questions surrounding track and temperatures, it looks likely that someone in the Mid-Atlantic will receive some snow. My first call snow map will be out tomorrow afternoon. Stay with JB Weather on Facebook and Twitter for the latest updates and most complete coverage!
Lead Forecaster -John A. Bordash Next Chance of Accumulating Snow: Saturday Afternoon into Sunday Probability of Accumulating Snow: >95% Moderate to Significant snow totals are likely to impact the Mid-Atlantic Saturday afternoon into the day on Sunday. This winter storm looks to set it's highest impact area in a zone from Central Virginia to Southern Maryland. Lesser, but still admirable, impacts will be felt further north towards the Mason Dixon Line. Shown above, I have increased my snow forecast to a healthy 4-7" throughout the region. Ahead of the storm, the National Weather Service has issued a Winter Storm WARNING for all of Southern Maryland and Tidewater Virginia. Winter Weather ADVISORIES are up for northern counties that will see lower snow totals. Those weather alerts are shown below. Our storm is currently developing in Texas. With the storm's current placement there, it is allowing for a nice flow of moisture from the Gulf of Mexico to occur. Cold air is pretty entrenched across the northern tier of the country; which is allowing that moisture to fall as snow. That is all shown below on the 5pm Friday radar snapshot. There is a weak northern piece of energy with this system. It is hard to tell, but that is helping in enhance those snows in the Midwest. That weak northern piece will start to race out ahead from the main storm. It will be that fast moving piece of northern energy that will bring the Mid-Atlantic an inital snow threat on Saturday. Generally, light snow will fall while the southern system tries to catch up. This is when northern areas could see a majority of their snow. I have that shown below with future radar stopped late Saturday afternoon. While some snow is possible, I do not expect much to fall in Southern Maryland and Tidewater Virginia on Saturday. It will be that main southern piece of energy that will deliver most of the snow to southern zones. The southern storm will begin to take over during the overnight hours of Saturday. By Sunday mid-morning, snow will be falling across the region. The heaviest and more moderate snows will be focused across Southern Maryland. That all is shown in the image below. In a change from yesterday's forecast, this system does appear that it will come a touch further north. That will allow for some heavier snow, thus the higher totals. Most areas of sleet and ice should be confided to Virginia. I believe that the high pressure to our north will keep our area cold enough for snow. The only concern I would have for some sleet would be across Tidewater Virginia and extreme southern St. Mary's County (south of Great Mills). Even that wouldn't happen until late. Shown in the planner below, this should be all snow, with the biggest impacts focused on Sunday. The impact from this storm looks to be moderate to high for our region, as shown below. The big question I know is coming is, "How will this effect operations on Monday?" School Odds will be released Sunday evening. However, impacts could linger into Monday, namely with travel. This will be the prominent across our region. Delays and closings are certainty possible on Monday from lingering impacts. Again, I will release more specific county-by-county school odds on Sunday. My-oh-my how this forecast continues to change. Just from yesterday, the snowfall forecast has increased for our region. I had mentioned yesterday that these southern systems do have a history of ticking north to give us some higher totals. Sure enough, that appears to be the case. Southern Maryland looks to be game on for some significant snow totals and impacts Sunday. I will continue to monitor this storm, and make any adjustments to my forecast as I see fit. However, I think this should be pretty close to my final call on this storm. I will have non-stop coverage on Facebook and Twitter to keep our community prepared and head of the storm. Stay with Southern Maryland's Most Accurate forecaster for updates!
Lead Forecaster -John A. Bordash |
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