FILE- In this March 10, 2017, file photo, pedestrians walk through wet snow in the Brooklyn borough of New York. The Northeast is bracing for winter's last hurrah — a blizzard expected to sweep the New... (Associated Press) 
 
 FILE- In this March 10, 2017, file photo, pedestrians walk through wet snow in the Brooklyn borough of New York. The Northeast is bracing for winter's last hurrah — a blizzard expected to sweep the New York region starting Monday, March 13, with possibly of being the season's biggest snowstorm. (AP... (Associated Press) 
 
 NEW YORK (AP) — A powerful nor'easter could bring blizzard conditions and more than a foot of snow to some parts of the Northeast, proving that winter is not done yet. 
 
 The National Weather Service issued a blizzard watch from late Monday night through Tuesday evening for New York City and parts of northern New Jersey and southern Connecticut, while winter storm warnings and watches were issued for the remainder of the Northeast. 
 
 Meteorologists said the storm could dump 12 to 18 inches of snow on New York City with wind gusts of 40 to 50 mph. 
 
 Mayor Bill de Blasio urged residents to avoid unnecessary travel and help keep the roads clear for sanitation crews and first responders. 
 
 "We're preparing for a significant storm on Tuesday, and New Yorkers should also prepare for snow and dangerous road conditions," de Blasio said. 
 
 Light snow is expected to begin late Monday night and intensify overnight into early Tuesday morning. The heaviest snowfall is expected Tuesday morning through the afternoon, with snowfall rates of as much as 2 to 4 inches per hour. 
 
 "This would certainly be the biggest snowstorm of the 2017 winter season in New York City," said Faye Barthold, a weather service meteorologist based on Long Island. 
 
 Boston also could get 12 to 18 inches, with isolated amounts of up to 2 feet across northeastern Massachusetts. 
 
 In Philadelphia, crews began treating some area roadways on Sunday. The city could see 6 to 12 inches of snow. The weather service said there is a chance the snow could change over to a wintry mix or rain for a time Tuesday morning, which could limit total snowfall amounts. 
 
 Farther south, in the nation's capital, where the National Cherry Blossom Festival is scheduled to start Wednesday, snow accumulations of 6 to 10 inches are expected. 
 
 Winter's last hurrah arrives just a week after the region saw temperatures climb in the 60s. ||||| Editor's Note: This story has been updated with new forecast information. 
 
 It’s been a tough winter for snow lovers. From Chicago to New England, February was actually hot in many parts of country. Daffodils and flowering trees have been blooming for weeks . So far in 2017, it’s been in the 60s or 70s as often as it’s snowed in New York City. 
 
 That’s all about to change this week. 
 
 One of the biggest March snowstorms on record appears poised to strike the East Coast on Monday night, packing strong winds and snow drifts measured in feet. It’s as if Mother Nature decided to make up for lost time and pack an entire season’s worth of winter into a single day. 
 
 A blizzard warning is now in effect for a large swath of the Northeast from Philadelphia to Portland, Maine, including New York City — meaning white-out conditions and tropical-storm-force winds are likely. A relatively sharp cutoff between snow and slush should keep the biggest snow totals away from Washington, D.C. and Boston, but elsewhere, totals will rack up to 1 or 2 feet. The latest National Weather Service forecasts show a wide section of the Northeast, from Maryland to Maine , on tap for more than a foot of snow. Snowflakes should start Monday evening around Washington, D.C. and reach their peak early morning on Tuesday in New York City before tapering off by Tuesday evening across New England. The storm will be a relatively fast-mover, with most of its energy concentrated into a period of about nine hours of heavy snow and strong winds at each location. 
 
 Besides heavy snow and strong winds gusting to nearly hurricane-force in parts of Massachusetts, the storm may bring at least moderate coastal flooding to parts of the New Jersey shore. The result will be a snow day for sure on Tuesday with schools and workplaces closed—the National Weather Service is warning that “several roads may become impassable” and those that travel should bring along a “winter survival kit.” NYC schools will be closed; the governor of Connecticut has issued a statewide travel ban. With leaves already out due to the early spring, there’s also a risk of widespread power outages . An experimental winter storm severity index used by the National Weather Service maxes out the scale: 
 
 While the effects on land may be astounding for at least a short while—words like paralyzing and crippling are being used to describe it—meteorologists are also viewing the storm as eye candy and refer to its weather maps as “ art. ” 
 
 From a weather nerd-out standpoint, the storm is close to perfection. The primary ingredients—a cold pulse from the Great Lakes and a low-pressure system forming off the Carolinas—will pull in subtropical moisture from a record-warm Gulf Stream right offshore . The storm will rapidly strengthen —in the process becoming a meteorological “bomb ” ( a technical term for rapidly strengthening low-pressure centers)—and travel over the sweet spot to maximize snowfall for New York City and New England. That’s forced meteorologists to add new colors to their weather maps, and marvel at an “ absolute crusher ” that will be “ puking snow .” An objective pattern-matching algorithm has compared this storm to some of the all-time strongest, too, including the Valentine’s Day 2007 blizzard and 1993’s “Storm of the Century.” 
 
 There’s even a good chance of thundersnow—the meteorological Holy Grail, made infamous by a viral Weather Channel video from 2011 in Chicago. 
 
 If you’re wondering, “but, it’s March—how is this happening?”—that’s a good question. If the current forecast—which was boosted early Monday morning by the National Weather Service—pans out, the storm will rank as the second-biggest March snowstorm in New York City history (records go back to 1869). Two studies published last year argue that climate change may be making the ingredients for big East Coast snowstorms more likely, and the evidence is starting to mount: Including this storm, eight of the 10 biggest snowstorms in New York City have occurred since 1996. High-resolution weather models continue to insist that most of this storm’s snowfall will come during just a few hours via an intense band with snowfall rates of up to 5 inches per hour—near the upper limit of what is physically possible along the East Coast. ||||| UPDATED9:30 p.m. ET: New computer model runs coming in this evening may change the storm total snow forecast somewhat, with the biggest alterations possible along the dicey northern fringe of the snow shield, near New York City, Connecticut and Boston. 
 
 However, the impacts of this storm on the mid-Atlantic region, including Washington, D.C., needs to be especially emphasized. The Capital Weather Gang blog put the upcoming situation this way in a post on Wednesday early evening: "Wherever you are Friday evening, it is quite possible you may need to remain there until Sunday or Monday, or even a bit longer." 
 
 Travel in the nation's capital, possibly all the northeastward into Philadelphia and central New Jersey, may become not just treacherous on Friday night and Saturday, but downright impossible. 
 
 It could be one of the top three largest snowstorms of all time in Washington, D.C., and Baltimore. 
 
 The storm, which the Weather Channel is calling "Jonas," is poised to blast the region with wind-driven heavy snow, sleet and perhaps some rain beginning on Friday and lasting straight through the weekend. The snowfall totals — some are predicting that more than 30 inches is possible — could rival those not seen since 1922, and possibly even breaking all-time records for the nation's capital, though that is far from a sure bet at this point. 
 
 Computer model simulations are unanimously showing double-digit snowfall totals for the nation's capital northeast to southern New Jersey. Each model has its own quirks, with some showing a 24-inch plus snowfall maximum on top of Washington and others favoring other locations. 
 
 If D.C. were to pick up 30 inches of snow, it would be the biggest snowstorm in the notoriously snow-phobic city's history, and would very likely cripple the region for days. However, other models, as well as historical records of how past storms behaved, show the heaviest snow hitting west of the I-95 corridor, toward higher-elevation areas where there is less of a chance of a mix with sleet or rain. 
 
 GFS model snowfall projection, with the highest amounts in the D.C. area, and lower amounts near New York City and Boston. Image: WeatherBell Analytics 
 
 What we know 
 
 There will be a powerful storm. 
 
 The storm will take shape across the southeastern states on Thursday night, tracking into the Mid-Atlantic on Friday. Blizzard watches and winter storm watches are already in effect for the Washington area in advance of the onset of heavy snow on Friday evening. 
 
 The snow will be extremely heavy in some areas. 
 
 In some places in the Mid-Atlantic, the snow is likely to exceed the rate of 1 inch per hour, and approach 2 to 4 inches per hour at times. Thundersnow — any winter storm enthusiast's dream occurrence — is also a possibility. 
 
 This storm is not likely to fizzle out or disappoint snow lovers in the Washington to Baltimore corridor, but... 
 
 
 
 People should keep their expectations in check. It is possible this will be a top three snowstorm for Washington, but that is not guaranteed. Many factors could come into play and somewhat hold down accumulations. Still, at least 1 to 2 feet of snow look very likely in the Washington area, with the potential for even more. 
 
 For historical perspective, consider that Washington has not had a 20-inch or greater snowstorm in nearly 100 years. The largest snowstorm on record for the city was in 1922, when 28 inches fell. 
 
 Most of the recent blizzards in the city, including the infamous "Snowmageddon" event of 2010, amounted to about a foot-and-a-half of snow. 
 
 Everything you need to know about DC snow. Which graphics will need updating after storm?! https://t.co/APZQYERXYr pic.twitter.com/gA2vg0nRt5 — Ian Livingston (@islivingston) January 20, 2016 
 
 This storm will have significant coastal impacts. 
 
 
 
 Due to strong onshore winds, high surf and an astronomically high tide from a full moon, this storm could do severe damage to some parts of the New Jersey shoreline. On Tuesday, the National Weather Service forecast office in Mt. Holly, New Jersey brought up the "S" word for the Jersey Shore, warning of storm tides possibly "within inches" of Hurricane Sandy levels. 
 
 That storm devastated the Jersey Shore, with residents and business owners spending millions in the years since to rebuild. 
 
 National Weather Service offices in the New York City area as well as New Jersey are forecasting moderate to major coastal flooding at the time of high tide on Saturday morning and evening. Exactly how high the water gets — and how much damage ensues — is not yet clear, since it depends on the timing of the strongest winds, wind direction and other factors. 
 
 'Interesting' Saturday along Del coast. Forecast low tide (black line on right) higher than normal high tide. pic.twitter.com/7rIqm8No65 — Gary Szatkowski (@GarySzatkowski) January 20, 2016 
 
 Warmer than normal ocean temps will also promote instability transfer of energy over water; i.e., stronger winds, bigger waves. Science! — Gary Szatkowski (@GarySzatkowski) January 20, 2016 
 
 As of Wednesday afternoon, predicted high tides in Atlantic City may peak at about the 10th-highest on record there, while possibly making the top 5 highest on record at Cape May, New Jersey. 
 
 Lower amounts of flooding are expected for New York City based on the expected wind direction from the north-northeast, compared to when Hurricane Sandy hit and the winds were pushing more of the water from southeast to northwest. 
 
 The current predicted high tides in Atlantic City Saturday evening and Sunday morning would rank in the top 10 highest on record there. Tides are likely to produce moderate to major flooding along the entire coast across at least three high tide cycles Saturday and Sunday, the weather service said. 
 
 The unknown 
 
 Where the heaviest snowbands will set up. 
 
 In storm systems like this one, narrow bands of heavier snow tend to form northwest of the low pressure center, and they help determine who gets the jackpot totals versus areas that see somewhat lower accumulations. Unfortunately, computer model guidance on where those bands will develop and persist is only accurate a few hours in advance, rather than 72 hours ahead of time. 
 
 What precipitation type we'll see. 
 
 Ocean temperatures off the East Coast are running unusually high for this time of year, partly because December was so warm in this region. It's likely that some coastal locations in the Mid-Atlantic — possibly including Washington, Baltimore, Philadelphia and New York City — could mix with sleet or rain for a time on Saturday. However, this depends on the exact track of the storm, as well as its mid- and upper-level energy higher in the atmosphere. And these details are tougher to pin down until the storm gets closer. 
 
 The mixing issue has often appeared suddenly in Washington during past snowstorms, including the blizzard of 2003, when sleet held the city's snow totals down significantly compared to areas north and west of the city. 
 
 Berie Rayno, a meteorologist with the private forecasting firm AccuWeather, said the lack of true Arctic air feeding into the storm and presence of milder-than-average ocean waters along the East Coast make the case for not overstating the snow potential for the nation's capital. 
 
 “Let’s be careful not to go overboard,” he said. “I just think there is so many things that the models are not going to handle, that I think you've got to be careful along the I-95 [corridor].” 
 
 Another southerly shift? 
 
 Some computer model runs have shown a tendency to shift the storm southward from previous projections, taking Boston and Hartford out of the main snow shield, and even putting New York City out of the 6- to 12-inch range. 
 
 As of Wednesday at noon, many weather forecasters with experience in the Philadelphia to New York region were still calling for at least a moderate snowstorm in the Big Apple. 
 
 Updated GEFS 12z forecast for snowfall DC 
 
 1 or 2 or 3 feet ... so take the median 18" pic.twitter.com/KbA0ENxrw9 — Ryan Maue (@RyanMaue) January 20, 2016 
 
 For example, Kate Bilo, a meteorologist for CBS in Philadelphia, said in a Twitter exchange that the sharp northern cutoff of the storm is "one of the toughest calls with this system," but that 6 to 12 inches up through New York City looks reasonable. 
 
 Rayno told Mashable that the southward trend in the model forecasts may very well reverse as the event nears. 
 
 “I think the trend south is going to be stopping and there will be trend north as we go through our Thursday and Friday,” he said. There's little question that the New York to Boston corridor will be the "fringe area" for this storm, Rayno said, but that his forecast right now is also for 6 to 12 inches in these areas. 
 
 What concerns forecasters 
 
 Weather forecasters across the country have been weighing in with each shift of computer model runs. 
 
 Much of the discussion reveals how serious of a threat this storm really is. For example, here's how the Weather Prediction Center, a unit of the National Weather Service (NWS), described the storm threat on Wednesday morning. This post applies to anticipated conditions on Saturday. (The ALL CAPS style is from the NWS.) 
 
 THE WINTER STORM ALONG THE EAST COAST SHOULD BE WELL UNDERWAY WITH 1 TO 2 FEET OF SNOW EXPECTED FROM THE APPALACHIANS ACROSS THE MID-ATLANTIC AND TOWARD NEW YORK WITH HUGE IMPACTS TO COMMERCE...TRAVEL...AND POSSIBLY LIFE AND PROPERTY. 
 
 The NWS in Mt. Holly, New Jersey highlighted the potential for "moderate to major" coastal flooding. The biggest threat for this appears to focus on the Saturday morning high tide. 
 
 Here's what one of its forecasters wrote: 
 
 THE SURGE GUIDANCE IS SHOWING A SIGNIFICANT WATER RISE SATURDAY, HOWEVER THIS WILL DEPEND ON THE WIND DIRECTION ESPECIALLY AT HIGH TIDE AS A MORE ONSHORE COMPONENT WILL HELP WITH WATER PILING UP. IN ADDITION, HIGH WAVE ACTION INTO THE COAST AND PRECIPITATION WILL TEND TO HOLD WATER AT THE COAST ADDING TO THE WATER RISE. THIS COULD LEAD TO PROPERTY DAMAGE IN SOME 
 
 AREAS AS WELL AS POTENTIALLY SUBSTANTIAL BEACH EROSION. HE DELAWARE BAY IMPACT FOR MODERATE OR MAJOR FLOODING IS ESPECIALLY HIGHER ON THE DELAWARE SIDE OF THE BAY DUE TO A POUNDING NORTHEAST TO NORTH WIND. THIS POTENTIAL WILL CONTINUE TO BE CLOSELY MONITORED AS THE DETAILS OF THE WINTER STORM BECOME MORE CLEAR. 
 
 Rayno said he's concerned that forecasts of more than 2 feet of snow near Washington and Philadelphia may be too high, considering many factors including the forecast track and intensity of the storm. 
 
 The Mashable science team will continue to update this story as the forecast changes throughout Wednesday.
– Residents of the Northeast have known that a storm was on the way for days now, but the forecasts are only getting more dire as the moment approaches. The National Weather Service has issued a blizzard watch from late Monday through Tuesday evening for New York City and parts of northern New Jersey and southern Connecticut, while winter storm warnings and watches were issued for the remainder of the Northeast, per the AP. Meteorologists said the storm could dump 12 to 18 inches of snow on New York City and Boston, with Philadelphia is expecting up to a foot. But as NBC News notes, the more dangerous component will be high winds on Tuesday morning, with gusts of 55mph to 70mph in the forecast. "This would certainly be the biggest snowstorm of the 2017 winter season in New York City," says a weather service meteorologist based on Long Island. In fact, it has the potential to be among the worst, if not the worst, March snowstorm in New York City history. Coastal flooding also is a risk along the Jersey shore and elsewhere, as is "thundersnow," explains the Daily Beast. Meanwhile, spring officially arrives on March 20.