It was both a trick and a treat as a rare – and in places unprecedented – Nor’easter developed on October 29, 2011 and dumped impressive amounts of snow across New England in the northeastern U.S. this past weekend. This amount of snowfall would rarely be seen in the months of January/February. Snow totals ranged from three to six inches up to nearly 30-plus inches within a 24-hour period. The snow affected millions of people, and left over three million people without power. The storm is the same system that was responsible for the snow across the state of Colorado and parts of northern Texas as it pushed east. The storm has delayed some areas across New England from Halloween festivities Monday. It shattered many records this past weekend, and will likely be known as the Halloween Snowstorm of 2011. How scary is that?
An area of low pressure surged into Colorado last week and provided two inches to nearly a foot of snow across Denver and Boulder. The system pushed to the east coast where a couple of key components met together to bring about a perfect snowstorm for the U.S. Northeast in late October. Does anyone remember Tropical Storm Rina? Rina dissipated over the Caribbean due to strong wind shear and dry air disrupting the organization of the storm. The “center” of the storm drifted to the south, but the moisture plume and the remnants of Rina was actually pulled to the north thanks to the strong trough digging into the eastern coast.
Behind this trough of low pressure, cold air surged to the south bringing chilly temperatures across the U.S. East Coast. The area of low pressure evolved off the East Coast as it moved towards New England, in the northeast. The combination of it rapidly intensifying, thus bringing colder air on the western side of the low and bringing in tropical moisture from the remnants of Rina help create the perfect Nor’easter across New England for the month of October 2011.
Some places had not seen snow in October since the Civil War back in the 1800s.
Meteorologists saw this event coming a couple of days before it happened. Granted, there were large uncertainties regarding snowfall accumulations across the region. Many of the model runs, especially the European model (ECMWF) saw an area of low pressure strengthening as it moves up the East Coast of the United States. It brought strong cold air advection behind the low, which allowed the rain to turn into mostly all snow during this event. The GFS model run (image below) showed a 981 millibar low off the coast of Maine. In reality, the low off the New England coast dropped to 975 millibars as of 1:15 a.m. EDT October 31, 2011 (currently over Nova Scotia). A pressure this low is equivalent to a strong Category 1 hurricane.
The Nor’easter brought strong winds across the region, but nothing too strong inland. Nantucket, Massachusetts recorded a 69-mile-per-hour wind gust, which is nearly hurricane strength (74 mph).
The reason for over three million power outages across New England is simple: it’s not winter yet. Many of the trees were still covered with leaves that had not fallen. The weight of the leaves, snow, and minor ice accumulations contributed to weighing down tree limbs, which eventually fell on power lines resulting in mass power outages throughout the region. At this writing (October 31, 2011), many people are still without power, and some places might not see power restored until the end of this week.
Snowfall totals were rather impressive, especially considering the ground was very warm and that the first, initial snow melted on contact. In regards of breaking records, Central Park in New York City broke their record of 0.8 inches set back in 1925 with an amazing 2.9 inches of snow. Many states shattered their old records for the most snowfall accumulation seen this early in the season. Here’s a look at some of the impressive numbers (in inches):
Peru – 32.0
Plainsfield – 30.8
Frostburg 1 N – 11.6
Sabillasville – 11.5
Action – 20.0
Bridgton – 17.4
Jaffrey – 31.4
Bow 1.6 NW – 25.8
West Milford – 19.0
Lake Hopatcong – 17.0
Millbrook – 21.6
Bloomingburg – 17.7
Hazleton – 16.0
Huffs Church – 16.0
West Glocester – 6.6
Skyland – 9.0
Big Meadows – 8.0
West Halifax – 16.0
Brattleboro – 15.1
Mount Storm – 14.0
Kirby – 12.0
Is this event foreshadowing this upcoming winter? It is very possible, but only time will tell if this is the first of many systems that will push into the U.S. Northeast. In my opinion, it will be a very interesting winter for New England, so hopefully everyone will be prepared for the worse and hoping for the best.
The loss of Arctic sea ice might be contributing to colder winters at this time. The greatest loss of Arctic sea ice occurred in 2007, and 2011 rivals that same year. According to the Arctic Report Card:
There continues to be significant excess heat storage in the Arctic Ocean at the end of summer due to continued near-record sea ice loss. There is evidence that the effect of higher air temperatures in the lower Arctic atmosphere in fall is contributing to changes in the atmospheric circulation in both the Arctic and northern mid-latitudes. Winter 2009 – 2010 showed a new connectivity between mid-latitude extreme cold and snowy weather events and changes in the wind patterns of the Arctic; the so-called Warm Arctic-Cold Continents pattern…With future loss of sea ice, such conditions as winter 2009 – 2010 could happen more often. Thus we have a potential climate change paradox. Rather than a general warming everywhere, the loss of sea ice and a warmer Arctic can increase the impact of the Arctic on lower latitudes, bringing colder weather to southern locations.
Bottom line: Snowtober! The Nor’easter that hit New England in the U.S. Northeast on October 29, 2011 was rare and in many places unprecedented. Many places have never seen this much snowfall prior to November or December. The mixture of a strong trough and tropical moisture from Rina enhanced the snowfall rates across New England. Some areas received over two feet of snow, which caused major transportation issues both in the air and on the ground. Over three million people experienced power outages as trees were weighed down by leaves and wet snow. Some areas might not get their power restored until the end of this week.
Weather is frightening, isn’t it? Happy Halloween!
Matt Daniel is weekend Meteorologist for 13WMAZ (CBS) in Macon, Georgia, and founder of the blog Athens GA Weather. He's a self-described "big weather and music geek" and has produced weather content for CNN, MSN Weather and EarthSky. He has a passion for helping to keep people safe when severe weather strikes and says if you don't have a NOAA Weather Radio ... you should get one.