Nov 13, 2012: Cooler Temperatures Continue

Brief Forecast Overview:

Following this morning's cold front which brought widespread showers, a colder air mass returned into the region today, with chilly temperatures sticking in place through the rest of this week into most of next week. In this time period, high temperatures will generally remain in the mid 40s to low 50s across the area. Lows will start out tonight in the mid 20s to low 30s away from NYC, with mid 30s in NYC and the immediate coast, although will gradually warm towards the weekend and next week into the low to upper 30s away from NYC, with upper 30s to low 40s in NYC and the immediate coast. Mostly to partly sunny skies will continue through the weekend.

The forecast becomes more uncertain next week with a coastal storm, with some models keeping the storm south of the region while others show rain reaching the Northeast. With the pattern in place, this storm will generally be slow moving; increased cloud cover and possibly rain are expected for early-mid next week, with the storm likely to exit the region towards late next week. Stay tuned for more information on this storm potential and the possible impacts in the area.

Nov 12, 2012: Chilly, Drier Pattern Coming Up

Forecast Highlights:

Following another warmer than average day, a cold front is currently moving through the region, with a chilly air mass returning by Tuesday. Chilly temperatures will continue through the next 1-2 weeks without any significant warmth or cold, while a coastal storm may affect the region next week, especially in the Mid Atlantic and potentially in the Northeast, with additional rain possible.

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Forecast Overview:

As the radar image above shows, a cold front is moving through the region with widespread showers. The rain should clear most of the area by the late morning except for the eastern half of the area, with colder highs expected for Tuesday peaking in the mid to upper 40s inland and the upper 40s to low 50s across the rest of the area. Dry conditions will persist through the rest of the week and into next weekend with little changes in the weather conditions across the region; highs will generally reach the mid 40s to low 50s for most days, with lows in the mid 20s to low 30s away from NYC, ending up slightly warmer by next weekend into early next week.

As mentioned with yesterday's pattern outlook, a more progressive and less amplified pattern will develop, with above average 500mb heights across the northern US with below average heights in the Southeast along with a potential coastal storm around early-mid next week. With the above average heights and a strong surface high pressure to its north, the low will remain suppressed, and at this time would be most likely to have possible impact in the Southeast, possibly extending further north into the Mid Atlantic. Frozen precipitation is not out of the question for interior parts of the region should precipitation make it this far north, but with an absence of widespread strong cold air which remains bottled up in Canada, this storm is unlikely to be a widespread snow producer. With the pattern in place, this is likely to be a slow moving storm, influencing the pattern across the region through at least mid next week. No significant change in temperatures appears to be on the way through at least late next week.

Long Range Pattern Outlook #4

Brief Overview:

Tonight's long range pattern outlook focuses on the second half of November, regarding the medium range pattern and the potential for a coastal storm, along with verification for the 1st pattern outlook from 10/6. The final winter outlook will be posted towards late November.


Click below to read the full post.

Nov 10, 2012: Warmer, Less Extreme Pattern Ahead

Forecast Highlights:

Following the extreme 10-day period ranging from hurricane Sandy to extreme cold and a significant early season snowstorm, the NYC area is finally getting a much needed break from the active pattern. A pattern change is currently unfolding, with much warmer temperatures returning this weekend into early next week as a less active pattern continues through at least the middle of November.

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Nor'easter Brief Summary:

For the 2nd year in a row, the NYC area was affected by an unusually early significant snowstorm, with widespread amounts of 4 to 10 inches, locally as high as 13-14 inches, observed. This storm was very difficult to forecast with the model guidance failing to reach a consensus on the storm scenario until the storm was already underway. While parts of the forecast from the night before did verify, such as the expectation for a widespread snowstorm across New Jersey, SE NY and CT, the heavy snow began earlier than expected, with the heavy snow axis east of the expectation as totals were much higher than expected. Parts of Long Island which were expected to receive rain ended up with as much as 4-8 inches of snow, parts of Connecticut and New Jersey received as much as 10-14 inches of snow, and even Central Park received 4.7 inches of snow; this makes this month the snowiest November since 1989 which also had 4.7 inches, tying it with that year as the 6th snowiest November on record; the top 5 snowiest Novembers in recorded history were all from 1938 and earlier.


Latest Forecast: Drier, Not As Cold

Fortunately, there is not much to say about the upcoming pattern which remains relatively calm, bringing a much needed break to the region after Sandy, unseasonable cold and an early snowstorm. A strong ridge is currently building over the eastern half of the US, with a much warmer air mass spreading into the region. This will result in a significant warm up as temperatures reach the upper 50s to mid 60s on Sunday and the low to mid 60s, locally upper 60s near NYC, on Monday. A cold front will move through the region on Monday night with scattered showers as a colder air mass returns behind it, with highs returning into the upper 40s to low 50s for most of the area on Tuesday, followed by more widespread lows in the upper 20s to low 30s away from NYC. These colder temperatures will continue through at least Thursday, with a gradual warm up late in the week into next weekend as highs return into the mid to potentially upper 50s range. The main highlight towards the medium range is the potential for a storm around next weekend or early next week, which remains uncertain at this time.

Nov 7, 2012 Storm Summary

November 7, 2012 Snowstorm

On November 7, 2012, a moderate snowstorm affected the NYC area with moderate to locally heavy wet snow. Typically, a storm of this magnitude is not unusual, with numerous bigger storms observed over the last few years. This event, however, was made notable due to several factors, including this being the second year in a row the NYC area observed an unseasonably early snowstorm, unusually difficult forecasting of the storm even 1-2 days in advance, and this wet snowstorm coming barely a week after hurricane Sandy devastated the Mid Atlantic coast.

Nov 7, 2012 Storm Updates

Updates will be posted on the nor'easter and unusual early season snowstorm currently affecting the area starting later this afternoon. A few brief Twitter updates will be posted before then, with blog updates on the storm starting in the late afternoon as well.

10:20 AM: concern growing for heavy snow this afternoon to begin a bit earlier than expected with accumulations a bit higher in the NYC area. Update will be posted at 11:40.

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Latest Twitter Updates:  (Scroll to the bottom of the post for blog updates)

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Blog Updates:

11:20 PM: The snow band impressively continues to hold in place over the NYC area, although it has slightly weakened over the last few hours and has become a bit more broken up. Regardless, this storm has significantly overperformed in terms of snow totals, with widespread totals of 5-10 inches, locally up to 12 inches, likely across parts of New Jersey, NYC, western Long Island, and western/central CT, with the highest totals over SW CT.

This is the last storm update for tonight. The snow will gradually weaken later in the overnight hours, with dry conditions expected by the morning. The next forecast update will be posted on Thursday evening.

7:50 PM: The heavy snow band continued to train over the immediate NYC area over the last few hours, with accumulations as high as 6-8 inches reported in SW Connecticut. Precipitation from the nor'easter has dried up across parts of the Northeast, although the band of heavy snow remains strong over the immediate NYC area, with lighter snow observed in NW NJ, Orange county in interior SE NY, and eastern Connecticut and Long Island. Additional power outages are being reported with the snowstorm on top of locations that remain without power due to hurricane Sandy a little more than a week ago, while winds were weaker than expected, generally reaching 40-50 mph in Long Island. The snow is expected to begin weakening after 8-9 AM, gradually ending through the overnight hours.

5:30 PM: A highlight of the winter came quite unexpectedly before the season even started, and in the strangest of all situations possible: A significant early season snowstorm in the NYC area a little more than a week after a late season hurricane in New Jersey. The current set up is somewhat east of yesterday's forecast, the northwestern parts of the area are underperforming, with Sussex and Orange county likely to end up with 1 to 3 inches total, with the lowest totals further northwest.

Instead, the heaviest snow is focusing in the area over NE NJ, NYC, western Long Island into Nassau county, and southwestern/central Connecticut, where the storm is significantly overperforming. Totals of at least 4 to 8 inches are expected across most of this area. The latest radar shows banding over NYC, Nassau county and SW CT, with the heaviest storm totals possible towards CT where amounts as high as 10 inches may be possible in some areas.

Current conditions will generally continue through the evening, with weakening snow likely towards the late evening and early overnight hours, with lighter snow mixing with light rain later into the overnight hours with temperatures staying close to the freezing mark. Mostly cloudy skies with isolated rain/snow showers are expected  for Thursday with slightly warmer temperatures, peaking in the low to mid 40s across most of the area.

1:30 PM: As of the latest observations, the heavy precipitation band is now near western Long Island and SW CT, approaching NYC and the north/western suburbs. Once the band crosses NYC, heavier snow will develop in the immediate NYC area for the rest of the afternoon into the evening hours while moderate to heavy snow continues in western Connecticut. The snow will continue through the evening hours before starting to weaken.

The updated snow map has been posted below. The heaviest snow totals will be across north central and NE NJ into SE NY and western Connecticut, where totals above 4 inches are expected. Isolated locations may see as much as 7 to 9 inches of snow under the heaviest bands.

11:45 AM: As expected, snow is starting to affect the immediate NYC area with some areas also reporting rain. The main  change in the expectation, however, is that the period of heavy snow originally expected for late this afternoon into the evening looks to end up a bit east of the original expectation while also moving in earlier than expected, affecting the immediate NYC area into central NJ and SW CT with moderate to heavy wet snow as early as 1-2 PM, even in NYC. This could be a big issue for locations where snow accumulates on the roads, with hazardous driving conditions for the afternoon and evening commutes.

At this time my forecast accumulations are similar to my map from last night but slightly adjusted upwards, with up to 1-2" likely in parts of NYC, and widespread 3-4+ inch totals across northern NJ, SE NY and SW CT, starting from the north/west suburbs of NYC. Totals may be as high as 6-8 inches in some areas.

Nov 6, 2012: Snow and Wind Expected Tomorrow

Forecast Highlights:

As the nor'easter that has been significantly complicated by unusually large differences in the model guidance approaches, there remains some confusion regarding exactly what it will end up doing, with the latest model guidance just 12 hours before the storm still not showing signs of agreement regarding the exact solution. Despite the uncertainty, there is more confidence that the area is dealing with a moderate to significant nor'easter tomorrow with strong winds for the coast and a wet snowstorm for interior parts of the area. Click below to read the latest analysis for the nor'easter.