December was the only month of the winter where snowfall was below normal for all climate and Cooperative Observer locations. Many areas received less than half the normal snowfall expected in the month of December, resulting in some of these areas having below normal snowfall amounts for the winter. January and February for most areas was near normal snowfall levels. The exception being well above normal snow amounts in January northeast of Lake Erie and Lake Ontario, primarily due to a large lake effect event with blizzard conditions at the end of the month.
Snow totals for the season were generally above normal in the lake effect areas and below normal elsewhere. This was primarily due to a repetitive feed of the very cold air into the nations mid section and Upper Great Lakes that later moved into our forecast area.
Direct shots of arctic air into the Lower Great Lakes are more favorable to multiple band events that cover a larger area versus larger snowfalls in the lake snow-belts. Temperatures for the winter of were near normal for all three climate locations and most of the Buffalo forecast area. Buffalo and Watertown were slightly colder than normal at 1. Rochester was 0. Temperatures at all three climate locations for November ran between four to five degrees Fahrenheit below normal.
Temperatures in December were between three and four degrees Fahrenheit above normal for Rochester and Buffalo, while Watertown was one degree above normal.
Temperatures for the three climate locations for the rest of the winter were within a few degrees Fahrenheit of normal. Below are tables for temperature records set at the three climate locations for the winter of The Winter of was not especially cold, nor snowy, for the bulk of western and north central New York. That being said, an unusually transitory polar vortex and a weak to moderately strong El Nino did allow for chunks of arctic weather to sweep across the northeast U.
This helped to support above average snowfall in the lake snow belts. While the forecast was fairly consistent through the period, there was a high degree of spread between the various ensembles that make up the final forecast. This led to a little more uncertainty in the forecast strength of the El Nino event. This is important to note because weaker ENSO events favor high amplitude patterns over North America, so not having a high confidence in the overlying jet pattern will severely limit the ability to forecast temperature patterns.
A higher amplitude flow would support arctic intrusions south of the international border and thus favor colder weather. On the other hand, strong El Nino events often result in a more zonal flow that floods the country with milder, Pacific modified air.
As it turned out, the ENSO event was probably just strong enough to prevent us from having a memorable season. A strong, persistent ridge was in place along the Pacific coast of the continent, while a deep trough was anchored over the eastern half of Canada.
This supported a seven week stretch where temperatures averaged well below normal to start the season. Bouts of snow came early and often, particularly during the second half of November when the highly amplified flow encouraged parts of western New York to receive snowfall that averaged more than a foot above normal. Interestingly, anecdotal evidence from past winters with similar ENSO events included cold, snowy starts that later transitioned to a prolonged period of relatively mild weather.
As we pushed deep into the heart of December though, an intense East Asian jet with winds approaching kts over the northern Pacific helped to batter down the staunch ridge that had dominated the west coast of North America. Meanwhile, the polar vortex eased across the Pole to the Russian waters of the Arctic Ocean.
This noteworthy hemispheric pattern change not only served to cut off the source of cold air into the Lower 48, but it allowed Pacific modified air to eventually reach to the Lower Great Lakes where temperatures averaged above normal for four solid weeks, including the holiday season. By the second week of January, a weak Greenland block supported the development of an upstream closed low over eastern Canada. The strong cross polar flow generated between this high latitude closed low and the re-emergence of the west coast ridge allowed arctic air to pour southward into the Great Lakes region where we experienced the coldest weather of the winter season.
Even though this was climatologically the coldest part of winter, temperatures STILL managed to average more than 20 deg F below normal on a fairly routine basis. This would be comparable to having daytime temperatures frequently reach the degree mark for a large stretch in July. The highlight of this pattern change was a lake effect driven blizzard over the Niagara Frontier directly supported by the polar vortex over Hudson Bay.
The overall hemispheric pattern was fairly persistent through the month of February. A broad trough was based along the Canadian border with a near zonal flow found further to the south over the Lower While there was a substantial ridge off the west coast, its axis was centered at least miles further out in the Pacific.
This all led to very changeable weather across the Lower Great Lakes, as temperatures experienced a roller coaster ride that included no fewer than six air mass changes. Despite the variation in temperatures though, mercury levels averaged well above normal for the month. March fell right in line with the trend of alternating cold and mild months, as the ridge over the eastern Pacific repositioned itself along the West Coast. This promoted a re-amplification of the general jet stream over the continent so that the door could once again be opened for cold air to move south from Canada.
The majority of the month averaged below normal…dashing the hopes of an early Spring. Following a cold end to October the month of November continued the theme of cool and damp days. Outside of a few short-lived warm spells, below normal temperatures characterized the month.
Snow averaged above normal for the month, with both lake effect and synoptic systems bringing accumulating snow to western New York. Temperatures averaged The warmest temperature this month was 62F degrees on the 6 th , which occurred during a brief warm spell. There were 27 days that remained below 50F at Buffalo…which is the greatest on record since records moved to the airport in This was the coldest Thanksgiving temperatures on record for both sites!
At Rochester, the mercury then dipped to 4F by daybreak of November 23rd, a temperature that has never been recorded that early in the season. Precipitation for November averaged well above normal. In fact, there were only two days without measurable precipitation at Rochester and four at Buffalo. This included 9 days of measurable snowfall at Rochester…more than double the normal and the greatest number since For cities like Philadelphia, New York, and Washington, DC, that have historically snowy winters, this shift in the average winter low means that snow and sleet could become rarer.
Critical water resources out west that depend on snow will suffer large declines. Average winter low temperatures, of course, obscure important details about how climate change is affecting winters, like how the cold is distributed throughout the season. So we also calculated how the number of days with below-freezing temperatures could change by in the same 67 cities.
You can see that by , these cities could lose a month or more of days with temperatures below freezing. And as we move further south, cities could experience even larger declines in the number of days with sub-freezing temperatures during winter:. And the sharpest projected declines in freezing days are actually in the Pacific Northwest:.
In general, scientists expect that winters will warm faster than summers across the US. This will have several major consequences that are pretty worrying. Animals like the snowshoe hare , found in the boreal forests of Alaska , undergo a seasonal molt from brown in the summer to white in the winter to camouflage with their environment. But less snow in the winter is making them more visible to predators. Changes in winter temperatures are also starting to affect our health and our water resources.
Bark beetles , for example, have devastated forests across the United States as temperatures have risen. In California, bark beetles combined with years of drought have helped kill off million trees across the state. And these dead trees pose a huge wildfire risk: They were one reason the deadly Camp Fire , which torched the town of Paradise, California, in November, got so big so quickly.
Critters that make humans sick are also benefiting from warmer winters. Cold winters have served as a key check on mosquito populations that carry viruses like dengue and Zika. Freezing temperatures can kill off mosquito larvae, reducing their numbers in the spring. Many plants also rely on temperature signals. Adult plants measure heat and cold to help determine whether to actively grow or go dormant.
Some flowering plants are already starting to emerge earlier in the season in part due to warmer winters. This is creating a mismatch between when a plant flowers and when insects like bees are around to pollinate them. Trump, who has repeatedly denied the science of climate change, has recognized the threats where some of his properties are involved. His golf resort in Ireland intends to build two sea walls and cited the risks of global warming in one of its applications for the construction.
Before his presidency, he called climate change a hoax and claimed the idea was perpetuated by the Chinese. The United States government and hundreds of scientific organizations agree that human activities are primarily responsible for global warming. Please upgrade your browser.
See next articles. A frigid morning in Chicago. Jose M. President Trump raises this question frequently, most recently on Jan. Trump realDonaldTrump January 29,
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