Tag Archives: autumn

NYC Weather Update + Winter Outlook – Oct 24, 2016

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Autumn weather is here in earnest. In a remarkable change from last week, we’ll see high temperatures below normal for most days. Temperatures will range 30ºF cooler than this time last week. As we look ahead towards the winter, there are mixed signals about whether this will be a cooler, warmer, or average winter.

Rest of today – sunny, breezy, with a high near 60ºF. Northwest winds around 15mph, gusting to 30mph.

Tuesday – mostly sunny, breezy again especially later with northwest winds again between 15-20mph. Cooler, with high temperatures in the mid-50s. With the wind, it will feel quite cool for this time of year.

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Wednesday – winds should ease up a bit, but will be cool again with high temperatures potentially only in the low-50s.

Thursday – temperatures rise back into the mid-50s with the approach of a storm system from the west that should bring a chance for rain, increasing through the day.

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Winter Outlook

Meteorologists are less confident that we’ll have a La Niña this coming winter, which makes the winter climate outlook more uncertain. There are indications that temperatures may be a bit milder overall. However, that doesn’t preclude the possibility of some serious cold spells also.

There are conflicting forecasts that call for a colder than normal winter also, which you can read about on Weather Underground. Unfortunately, there is no indication we’ll get above average precipitation, which would be welcomed considering most of the Northeast is still dealing with an increasingly serious drought.

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NYC Weekend Weather – Sept 22, 2016

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Today marks the official start of astronomical autumn, even though it will feel anything but fall-like today. Temperatures cool off considerably this weekend, which will lead us into a period of average to below average temperatures for the next week or so.

Rest of today – warm with high temperatures in the low-mid 80s and sunny skies.

Friday – warmer still with high temperatures in the mid-upper 80s and mostly sunny skies. Small chance for showers overnight as a cold front encroaches from the west.

Saturday – with the aforementioned cold front swinging through, we will get a noticeable change in airmasses from a more humid, tropical influence we’ve felt the last few days, to a drier, cooler, continental airmass from Canada. The resulting swing in temperatures will be dramatic, with high temperatures on Saturday ranging 10ºF lower than Friday in the mid-70s.

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Sunday – one of many sunny, fall-like days coming with temperatures in the low-mid 70s.

Monday – almost a clone of Sunday, sunny with highs in the low-70s.

NYC Weather Update – Oct 28, 2014

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Summary

This week will be archetypical of autumn weather, with large temperature swings in store for the region. We’ll start off with highs more characteristic of late summer near 70, though with clouds overhead, we may not top that number. A weak cold front will push through tomorrow with some chance of showers. Behind this front, temperatures will drop to more seasonable highs around 60 with dry conditions. The week ends like winter with an arctic airmass invading the region, leading to the possibility of snow and high temperatures only in the upper 40s.

Wednesday – clouds build in and showers will be possible for most of the day. Most rain should conclude by the evening hours. High temperatures will remain warm ahead of the passage of the cold front with winds from west pushing warm air ahead of the front.

Weak cold front passing through Wednesday, scattered showers possible.
Weak cold front passing through Wednesday, scattered showers possible.

Thursday – clear and sunny skies behind the cold front passing Wednesday, high temperatures cooler near 60. Overnight lows will be quite cool in the lower 40s with good conditions for radiational cooling.

Friday – clouds will increase ahead of the next storm system, and high temperatures will remain near 60.

Saturday – an intrusion of arctic air accompanying a strong, deep trough (cold front) will set the stage for what should be a raw, chilly, winter-like day. With the arctic air pumping in, high temperatures will struggle to even hit 50. In the chart below, you’ll see a height of 540 near us. Without going into too much detail, low heights generally correspond to colder temperatures, as colder air is more dense, it takes up less volume than the same mass of warmer air. A height of 540 is considered by forecasters to be important when determining precipitation type, as it indicates temperatures cold enough to support snow. That’s right – we will probably see some snow north and west of the city, and depending on the track of a secondary low that forms Saturday along the coast, we could even get some of the white stuff in NYC. This is a complex system, so it will bear watching over the next couple days.

 

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NYC Weekend Weather – Oct 18, 2014

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We get one last day of late summer-like temperatures today before autumn comes back with a vengeance. A cold front has already passed through the city and you can already notice the winds beginning to shift to the northwest. This will herald a much cooler temperature trend. For the remainder of today, we can expect temperatures near 70 with some clouds building behind the front. There could be a sprinkle or two but nothing serious.

Sunday forecast map
Sunday forecast map

Sunday will be noticeably more cold with high temperatures struggling to hit the mid-50s and with a gusty northwest wind. Gusts could top 30mph at times with sustained winds 15-25mph. Overnight lows into Sunday and Sunday night will be downright chilly in the 40s. Some interior areas could see frost Sunday night.

Monday the winds will abate as the pressure gradient between the departing cold front and high pressure to the west eases. Temperatures will remain cool at only around 60.

Tuesday and into later this week we will see the impact of a frontal system that moves through from the Great Lakes and develops as a coastal low off the Mid-Atlantic. Current models seem to suggest that this low will linger for a few days offshore, so we could see multiple rounds of rain as bands rotate around the storm center.

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Winter Climate Outlook

The Climate Prediction Center has released its 3 month temperature and precipitation long range outlooks for the months ahead. As you will see, CPC has the NYC area in a zone of 33% chance of seeing a wetter and warmer than average winter. Call it a hunch, but I still think we’ll get a couple nasty Nor’easter type blizzards. Warmer than average of course doesn’t imply we won’t get freezing temperatures. A slightly warmer atmosphere would allow for more moisture and energy for coastal storms to feed off.

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NYC Weekend Weather – Oct 2, 2014

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Friday and Sunday will be the sunny and pleasant bookends to what will be a stormy and rainy Saturday this weekend.

Today – we’re looking at sunny skies and high temperatures in the low 70s. Clouds will begin to build back in later in the evening as the storm maker for Saturday begins to move in from the west.

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NAM high resolution model output for Saturday at 10AM EDT
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Weather Prediction Center forecast map for Saturday

Saturday – a negatively tilted frontal system will be moving over the area Saturday, with the worst of the rain coming between about 10AM-3PM. We will be in the vicinity of a triple point (junction between a cold, stationary, and occluded front, this feature is common with mature mid-latitude cyclonic systems) that will be draping south from a strengthening low pressure center that will be moving northeast into Ontario during this timeframe. A thunderstorm is not out of the question given the atmospheric dynamics. Temperatures should hover around the 70 degree mark despite the cloud cover and rain because of the potential for us to briefly enter a warm sector between the stationary front and cold front.

Sunday – we get a crisp blast of autumn air behind the frontal system passing through Saturday. Sunshine returns just in time for the annual BikeMS NYC, which yours truly will be participating in. Cool temperatures will be only in the mid-upper 60s.

Monday – good weather sticks around for the start of the work week with high temperatures around 70.

Our next chance for precipitation should come Tuesday-Wednesday. The low pressure center responsible for the rain Saturday is forecast to close off and retrograde (move west instead of east, with prevailing upper level winds) over central Canada. An impulse of energy will rotate around this center and lead to another cold front passing through our area.

 

NYC Weather Update – Sept 23, 2014

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Today marks the first day of astronomical autumn, and it has been feeling ever more fall-like the past few days.

Wednesday – the day should start off partly cloudy, and high temperatures will sit at right about 70. However, with a coastal low forming off the Mid-Atlantic, cloud cover will increase especially later in the day.

NAM high resolution model output for Thursday, 9/25 @ 11AM EDT.
NAM high resolution model output for Thursday, 9/25 @ 11AM EDT.

Thursday – a slow moving coastal low (technically a Nor’easter) will be moving over the NYC region during the early morning hours Thursday and throughout the course of the day itself. With the low pressure center just to our south or southeast, we should see a cool northeast wind off the ocean. This will limit high temperatures to only the upper 60s under cloudy skies and periods of rain.

Friday – with this coastal low out of the way, high pressure will take control again and clear the way for a superb start to the Rosh Hashanah weekend. Highs on Friday should bounce back nicely into the mid 70s under clearing skies.

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GFS model output for Saturday, 9/26

Saturday – high temperatures will continue climbing to nearly 80 on Saturday under clear skies.

Sunday – pretty much a carbon copy of Saturday. High near 80.

The next chance at rain will be next Tuesday with a cold front approaching us from Canada.