bluewave

While 90s have always been rare in April, the highest maxes for the month have been steadily increasing.

That’s a function of the all or nothing snowfall regime which began in the 1990s as the winters have warmed. To reach normal to above normal snowfall has fallen squarely on the shoulders of BM storm tracks which most times were NESIS ranked KU events. The years without BM tracks and KU events were duds since the 1990s and the years with BM tracks were great. Since we lost the BM storm track in 18-19, nearly all the seasons with the exception of 20-21 around NYC were well below average. This is the risk of relying exclusively on one type of storm track to reach normal seasonal snowfall. When it was much colder from the 1960s to early 1990s we had a wider variety of storm tracks to reach average. So plenty of very cold winters without benchmark KU events broke even. These were the moderate storms with took BM tracks but didn’t rank on the KU scale. So in a colder climate we were able to nickel and dime our way to close to normal. These days nickel and dime events which were frequent this past winter just couldn’t get the job done since the storm tracks were so warm on the days with precipitation over .25 around NYC.

Those correlation composites are outdated since they were before we began to see the climate shifts in recent years. So newly emergent patterns will always have smaller sample sizes to draw from than from a colder stable era over decades and decades. January 2025 was one of the strongest -NAO winter months of the 2020s with very little snow to show for it. Same went for March 2023 with a strong -NAO.

We had great snows during the +NAO winters in 04-05, 13-14, 14-15, 15-16, 16-17 and 17-18. So the Pacific Jet has had more influence than the teleconnections in determining the BM storm tracks and snowfall in this area. The -NAO only helps snowfall when the Pacific Jet relaxes and the -NAO doesn’t link up with the Southeast Ridge.

It would be cool if you knew someone in one of these towers that would let you come over during high wind events.While I wouldn’t want to experience it all the time, it would be interesting to see what it was like at least once. Almost reminds me of one of those theme park attractions. I actually had a fiend who lived in the West End of Long Beach in a 2nd story unit which was built on lally columns. His ceiling lamp would sway and he had creaking noises when the winds went over 50mph. https://www.dezeen.com/2021/02/05/floods-and-high-winds-plague-residents-of-rafael-vinolys-432-park-avenue/

Yeah, the record SST warmth to the east of Japan when coupled with the Siberian air masses to the west over Northeast Asia really increase the gradient and Jet Stream across the Pacific. This leads to storm tracks cutting through the Great Lakes, hugging the I-78 to I-84 corridor, or getting suppressed to our south.This is why Philly to Boston experienced the lowest 7 year snowfall totals since 18-19 since the BM tracks have been missing. In the much warmer climate since the 1990s, we haven’t had an average to above an average snowfall season without an active 40/70 BM storm track. Prior to the 1990s we could get to closer to average snowfall without the BM tracks since the air masses were cold enough for more significant front end snows with the hugger tracks before the changeover occurred. We also used to get more snowy clippers in those days dropping to our south. But this storm track has shifted closer to the Great Lakes. Perhaps in the coming years we can find a way to shift the warm pool east of Japan a bit and allow that Jet to back off a bit. But it’s really a big unknown with the way the subtropical oceans have seen record warming in recent years. There was a record BM storm track from 09-10 to 17-18. This shifted to the opposite extreme since 18-19. We are reminded what happened with the storm track shift west of the APPS for State College. They had a record snowfall regime from the 60s to 90s with many historic inside runners just east of the APPS. That track had pretty much become dormant since 03-04. So there snowfall has been in steep decline since then as more storms are cutting west of the mountains now. We just don’t know enough about forecasting very long range storm track patterns to determine if the BM storm track goes the way of the inside runner east of the APPS or we can see at least some intermittent BM tracks in the coming years.

Yeah, the flooding has been terrible in those areas. A warmer atmosphere holds more moisture.So all the Great Lakes cutters focus the heaviest rains in those areas with the Gulf Inflow from the record SSTs there. Rainfall has been closer to average here recently as these systems tend to dry out crossing the mountains. So we have been spared the extreme flooding.

These combinations add an extra layer of complexity to what used to be more straightforward seasonal forecasts. So we get these competing influences which result in hybrid ENSO and PDO patterns. December really set the tone of the winter with the very impressive +PNA combined with the very fast Northern Stream of the Pacific Jet. You can see the WPAC forcing getting stretched east of the Dateline with the the SST warmth in the EPAC to Caribbean which we don’t normally see during La Ninas which usually have stronger subsidence there. So in effect we had competing marine heatwaves across the Pacific resulting in all these overlapping features. It makes it more challenging to get a clean ENSO and PDO response since the warm pools are in competing areas for the forcing to gravitate toward.

Your local area rainfall is also a function of the general pattern across the U.S. which has been much drier than average. It’s not a major drought by any means since the NYC system is in good shape but some of the NJ reservoirs are lower than average. More of an issue for gardeners and agriculture. Plus it doesn’t take much drought in the warm season for a feedback situation to enhance the warmth. Like we saw in the summer of 2022 and the fall of 2019. Plus the record 80° warmth on Long Island a few weeks ago could have had some feedback influence when combined with the downslope flow.

This was the first time after such a strong El Niño that Nino 1+2 continued to run so warm like we are seeing now. It’s quite possible that it contributed to the unusually strong +PNA we experienced this winter. But since the WPAC was so warm the NPAC Jet continued to dominate. So a bit of a combo between Niña-like and Nino-like influences. A variation on the 23-24 theme with the record Nino ridge in Canada interacting with the Nina-like warm pool in the WPAC causing the ridge to push further into the East like we typically see with La Ninas. So these combo patterns have resulted in below normal snowfall both winters from Philly to Boston.

We need to shift to a heavier than average rainfall regime to erase the drought.

Looks like the OP for next weekend is a cold outlier among its ensembles as the low should be further north instead cutting off south. But it still looks like more rain will be possible. The good news is that it appears like the drought could possibly be behind us. But we will need confirmation either way next several months to confirm. OP looks too cold vs ensemble

You simply aren’t reading my posts throughly. Instead you reply to me with responses based on how you want to answer determined by your predispositions. Waiting longer to measure the snow in the old days in fact resulted in lower measurements due to settling and compaction. So over time until the 1950s at some observing sites the 1990s snowfall measurements were taken post compaction. These days the measurements are done pre compaction. The resultant difference results in today’s measurements yielding 15 to 20% higher readings than the older ones. So guess what happens when you boost the older snowfall totals to account for this disparity in measurements? More stations than are already in long term snowfall decline show a steeper decline. The no trend stations show a downtrend. And stations with an increase have a lesser increase. As per the warmer atmosphere holds more moisture discussion you raised you are correct in one sense. Yes the warmer atmosphere and SSTs boosted snowfall totals during the 2010s. Plus we had a record number of benchmark storm tracks. So the snowfall totals during the 2010s were legit. But the older measurements would show higher totals using todays more frequent measurements. Remember we are talking about comparing the first order sites from the old times to new times. Since spotters and coop observers come and go over time and change locations. Plus the atmosphere was much colder in the older days. This allowed for less mixed precipitation and a greater percentage of total precipitation to fall as snow. So this in effect tried to balance out the less available moisture in a colder world. Plus the ratios were generally higher in those days since the atmosphere in the key dendritic growth layers was also colder. So using melted down snowfall gauge measurements and applying a simple 10:1 for events like the 1888 blizzard is a primitive way to measure snow based on modern understandings of meteorology. Just because no formal reanalysis of earlier snowfall hasn’t been done yet like has been done for hurricanes based on modern wind measuring analysis and correction doesn’t mean that those old measurements are untouchable and pristine as you suggest.

Light snow on the 12th to 13th. But getting 3 days or more in a row with 1.00”+ of precipitation is very rare. That’s why long range models often spread the heavy rain out too much over multiple days. As we usually have the rain focus more on 1 day or 24 hr period with nuisance rainfall or drizzle on the other days. Number of Consecutive Days Precipitation >= 1.00 for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. 1 4 1975-09-23 through 1975-09-26 2 3 2018-11-24 through 2018-11-26 - 3 2005-10-12 through 2005-10-14 - 3 1977-09-24 through 1977-09-26 Number of Consecutive Days Precipitation >= 1.00 for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. 1 4 1975-09-23 through 1975-09-26 2 3 2021-08-21 through 2021-08-23 - 3 2005-10-12 through 2005-10-14 - 3 1984-05-28 through 1984-05-30 - 3 1944-09-12 through 1944-09-14 - 3 1938-09-19 through 1938-09-21 - 3 1933-08-21 through 1933-08-23 - 3 1920-02-04 through 1920-02-06 - 3 1889-07-30 through 1889-08-01 - 3 1882-09-21 through 1882-09-23 Number of Consecutive Days Precipitation >= 1.00 for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. 1 3 1998-05-09 through 1998-05-11 - 3 1989-08-11 through 1989-08-13 - 3 1988-07-19 through 1988-07-21 - 3 1984-05-28 through 1984-05-30 - 3 1946-07-21 through 1946-07-23 - 3 1944-09-12 through 1944-09-14 - 3 1938-09-19 through 1938-09-21

Most of the rain fell on the 11th. Data for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. 1992-12-10 0.45 1992-12-11 2.55 1992-12-12 0.20 1992-12-13 0.05 Data for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. 1992-12-10 T 1992-12-11 2.65 1992-12-12 0.34 1992-12-13 0.02

But mesoscale banding and sharp snowfall gradients are nothing new with the biggest snowstorms. The commentary is more about changing measurement methods over time. So if many older snowstorms occurred today the amounts would be higher than the what appear in the records. Since there still hasn’t been a snowfall reanalysis to correct the old low biases.

It could turn out to be most of the rain falling on one day or 24 hr period with just nuisance showers and onshore flow the other days.

They are only universally inflated relative to the earlier era since the measurement methodology changed. https://www.wunderground.com/cat6/US-Snowfall-1900-2019-Decade-Decade-Look As anyone who has followed my blogs for WU over the past ten years has no doubt noticed, I am always interested in the actual data-derived records so far as weather events are concerned. In my previous post, I looked at record snowfalls for all the states and several cities for various periods of time (24 hours, monthly, etc.). In the conclusion to that blog, I wrote a bit on how climate change may be affecting snowfall in the United States. The basic conclusion was that no one really understands much about this. So, as a follow-up to that, I decided to look at how much snow has actually been measured decade by decade at 40 different cities/sites across the contiguous U.S. since 1900. I only included places that see winter snowfall regularly (i.e., in most years), meaning along and north of a line from North Carolina through Tennessee, Oklahoma and the mountainous regions of the West. A constraining factor in choosing the sites is that they must all have a continuous monthly snowfall record dating back to at least 1900, something that a surprisingly few do. There is no complete record for Nashville, Tennessee; Roanoke, Virginia; Sheridan, Wyoming; and Seattle, Washington, among other cities that would seem to be obvious choices. For instance, in the high mountain areas of the West there are virtually no sites with a continuous period of record (POR) back to 1900, aside from Flagstaff, Arizona; Donner Summit in the high Sierra of California; and Red Lodge, Montana (which I did not include because of its obscurity). Inherent problems with the data As noted in my previous blog, the methods of snow measurement in the U.S. have changed over time. An articleauthored by Matt Kelsch of NCAR/UCAR and official COOP observer for Boulder, Colorado, explains how in the oldest of snow records (mostly predating 1950) a simple 10-to-1 snow-to-liquid ratio was often used to estimate the snowfall (i.e., 1” of melted precipitation = 10” of snow). As it turns out, the average ratio for the contiguous U.S. is roughly 12:1 or 13:1, and that ratio can vary greatly from place to place and storm to storm, even within a single storm. At some point—and that point in time was different among the various weather observation sites—actual snowfall began to be measured using a stick-like ruler, with the snow measurements made either at the end of each snowfall or at one or more regular times each day (e.g., at 7 a.m. or 7 p.m.). At some point (and this is the problem with my data: that this “point” in time varied from site to site between the 1950s and 1990s), snowboards came into use (see Mr. Kelsch’s description of these in his writeup). The use of snowboards led to snowfall being more accurately measured, but it also increased the amount of snow attributed to any given storm. This is because snowfall measurements were now being made as often as every six hours (when the snow board would be cleared to make way for the next six-hour measurement) instead of just once or twice a day. Since deep snow settles as it falls, this method increases the amount of snow measured. As an observer who has used both techniques during his now-29-year COOP tenure in Boulder, Mr. Kelsch estimates that for extreme snowfalls the use of six-hourly snowboard measurements can result in snow totals that are 15 to 20 percent greater than what is actually measured on the ground. The potential for confusion became evident after New York’s official Central Park site reported a 24-hour snowfall of 26.8” on January 22-23, 2016, a new all-time record for New York City. That total was adjusted upward even higher, to 27.5”, after an NWS review found and corrected an error in the transmitted snow report. However, local weather-minded residents living near the site in Central Park (and there are many of those!) measured only 18” to 22” on the ground at the end of the storm. At Newark International Airport, observations from the same storm showed a preliminary record of 28.1”. That total was declared invalid by the NWS because the private contractor who measured the snowfall took snowboard measurements once per hour, as opposed to the standard six-hour interval. The revised total of 24.0” fell short of the record of 25.6” set on Dec. 26, 1947. Another example: The great Blizzard of March 1888 brought Central Park 2.10” of melted precipitation, resulting in the official 21.0” snowfall reported. Since temperatures during the height of the blizzard were in the low teens, it is likely that the ratio was much greater than 10 to 1, and thus the actual snowfall considerably more than the 21.0” officially reported. There is also the issue of observation sites moving from one location to another over time. This is one reason why Marquette, Michigan, is not in my list: their average annual snowfall almost doubled when the NWS office moved from the town to the hills several miles south. The bottom line is that comparing old snowfall measurements with new ones is comparing apples to oranges and, unfortunately, makes looking for historical trends (especially when talking about climate change) a hapless enterprise.

The recent issue with the Central Park snowfall measurements isn’t about 12 or 24 hour measurements like they did from the late 1800s into the mid 1900s vs more frequent measurements today. It’s that the warmer recent winters caused the snowfall to melt before the 6 hr measurements were taken. So they waited until several hours after the snow stopped to measure when some of it already melted. They should have at least measured when the snowfall stopped instead of waiting hours and hours to measure after when the temps went above freezing.

Probably correct since it looks the storm track returns to the Great Lakes right after.

4 days in a row with an easterly component to the winds will attempt to push back against the record westerly flow since December.

Not sure but New Haven probably would have had over 110” rather than the 95” report in 1779-1780 if they measured as frequently as today since the snowfall at the end of storms compacted 15-20% vs more frequent measurements of today. https://www.nps.gov/morr/learn/historyculture/hard-winter-news.htm A teacher in Yale College (New Haven, Connecticut) recorded approximately twenty days with snowfall, and a total of 95 inches of snow that winter. People walked across the Sound from Stanford, Connecticut to Long Island. Others walked from Rhode Island mainland to Block Island. Chesapeake Bay and the York River in Virginia froze over for the first time since Europeans settled there. Many people mentioned in letters that they could not remember a winter as bad.

The issue isn’t your experience with the measurements during recent times but how snowfall was measured before your time from the late 1800s to the 1950 to 1980 period.

Looks like a one-off as the long term EPS forecast bias has been cold especially day 11-15.

The Pacific Jet begins to relax in the spring allowing more STJ interaction.