bluewave

If Monroe was this bad, then I am sure that the area around Laurelton and Lido Blvd was even worse.

Still looks like the subsurface hasn’t made much progress beyond the late winter into spring OKW which peaked back in June. Took a few months in August for 3.4 to get to the strong level with the decent WWB pattern. But the lack of WWBs lead to the late September decline. So there is still no indication yet of another major OKW which would be important to get to super. Not sure how much warmer we can get from the recent +1.7 peak on just sloshing back and forth.

Sorry to hear about all that. The Sandy surge stopped 2-3 inches below coming into my old apartment which I had moved out of months before. Several of my neighbors that lived in older houses that weren’t on a higher foundation flooded. I can also remember a flash flood around the fall of 2015 that flooded a friends basement in Wantagh. I believe it was a back building thunderstorm that stalled right over Wantagh. I agree this was much rarer back in the old days.

Yeah, it’s not easy living on a barrier island these days. I got flooded out of my basement apartment in Long Beach by Agnes in June of 1972. We found a new apartment about a year later and settled on no more basement apartments. The rest of the 70s were relatively quiet for flooding outside the West End. My friend with a basement in his house picked up flooding with the spring 1983 deluge. Then the record 5.15”in under 2 hours shut down our drinking water during June 1995. Flooding situation was pretty quiet for another 10 years until the October 2005 record event which flooded out most LB basements. Followed up a while later by the record 10” in less than 12 hours on 8-14-11. Then the Irene storm surge flooding a few weeks later. Then the off the charts extreme Sandy tidal surge flooding in October 2012. I moved out of LB by chance months before Sandy hit. So not sure about all the local flood specifics after that time.

For this reason as well as others, I would transition all the CPC teleconnections to 500 mb height anomalies like this great recent paper.

The official OISST still has 3.4 under +1.5 as it has been moving sideways the last few days after the decline. Nino 1+2 and 3 cooled off in recent days. The only significant move up was in 4. Pretty much reflects that big +30 C reservoir near the Dateline. I believe this may be close to the all-time daily record for 9-30. https://cyclonicwx.com/sst/

Yeah, I am thinking there there were spots in the 5 towns and Far Rockaway with around 11.00” since the radar estimate in Valley Stream was around 2.50” too low. Nassau County... Valley Stream 9.06 in 0906 PM 09/29 CWOP

NYC is the new Riverhead. Data for September 1, 2023 through September 30, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Mean Avg Temperature NY PORT AUTH DOWNTN MANHATTAN WALL ST HEL ICAO 72.4 NJ NEWARK LIBERTY INTL AP WBAN 71.4 NY LAGUARDIA AIRPORT WBAN 71.3 NY MONTAUK AIRPORT WBAN 70.5 NY WORLD TRADE CENTER WBAN 70.4 NY MOUNT SINAI COOP 70.2 NY FARMINGDALE REPUBLIC AP WBAN 70.1 NY NY CITY CENTRAL PARK WBAN 69.7 NY RIVERHEAD RESEARCH FARM COOP 69.7 NY JFK INTERNATIONAL AIRPORT WBAN 69.6 CT NEW HAVEN TWEED AP WBAN 69.5

Yeah, the big EPAC forcing has always been just two weeks away since the spring. Reminds me of the proverbial GFS 384 hr snowstorm thst keeps getting pushed back in time. Euro seasonal forecast for September Verification

I miss the old days when the NWS were in 30 Rock and they would go over to the park for measurements and make sure tree growth wasn’t impinging on the observations.

At least to me, it’s more an issue of the long term integrity of the site than any climate change influence. Up through the 1980s, there was much less obstruction from trees. So comparing the pre-90s new ASOS observations to today is more like a change of location. So it’s hard to compare changes over time since fundamental way of measurements were taken there has changed. So artificially cooled lower highs during the leaf out season and more potential errors in measuring rainfall with trees sheltering the rain gauge and leaves possibly falling into the gauge. Plus professional snowfall measurements by NWS staff before they moved to OKX in the early 90s. To more sporadic measurements at times by different organizations that often measure too late after small snow events allowing the melt to lower the snowfall amounts. The article below is from 20 years ago and the tree growth has only increased. http://www.weather2000.com/ASOS/NYC_ASOS.html Central Park Weather: Vegetative Overgrowth Affecting Weather Readings - WABC-TV (New York-WABC, August 22, 2003) - Forecasting the weather is not easy. Government equipment can often be blamed for giving faulty weather information. As Bill Evans explains, a big culprit may be some of the equipment buried in Central Park. Rainfall, snowfall, and the temperature are all vital information recorded 24 hours a day at the weather station located in the heart of Central Park. But meteorologists like Michael Schlacter have serious concerns about the accuracy of the stations data. It sits amid overgrown vegetation and he says thats the problem. The leaves can trigger snow gauges and trees can warp rain and wind measurements. On this hot day, a temperature gauge is in the shade instead of direct sunlight. Michael Schlacter, Weather 2000: "Its kind of like driving a car without a speedometer, odometer, and gas gauge. You are running with false information." The weather instruments at Belvedere Castle have long adorned the top. There used to be a government meteorologist here in the city to keep an eye on them. But now the nearest meteorologist is 60 miles that way. But National Weather Service meteorologists say they knew the weather readings in the park would never be as keenly accurate as the ones at the airports where guidelines prevent foliage from being within 100 feet of the station. Schlacter: "We knew that at times we would have flaky readings, that leaves would fall in gauges, that we would have problems with visibility sensors." [NWS Meteorologist-in-Charge Michael] Wyllie says the weather station is there because it was historically significant to maintain its presence in the park. He says theres been a lot of growth because of the wet spring at so much in fact that temperatures have routinely been recorded lower in the park than at the airports. Wyllie: "We are actually having a micro climate system there because of the vegetation." Imperfect perhaps but nonetheless the system provides the official record of weather for the country's largest city. And Michael Schlacter says its a city that deserves better. Schlacter: "I think New Yorkers deserve a lot better, and I think they deserve the best weather station money can buy." Copyright 2003 ABC Inc., WABC-TV Inc.

Even with the cool and wet ending to the month, several stations will finish with another 70° September. Data for September 1, 2023 through September 30, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Mean Avg Temperature NY PORT AUTH DOWNTN MANHATTAN WALL ST HEL ICAO 72.4 NJ NEWARK LIBERTY INTL AP WBAN 71.4 NY LAGUARDIA AIRPORT WBAN 71.3 NY MONTAUK AIRPORT WBAN 70.5 NY WORLD TRADE CENTER WBAN 70.4 NY MOUNT SINAI COOP 70.4 NY FARMINGDALE REPUBLIC AP WBAN 70.1 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2005 74.9 0 2 2015 74.1 0 3 2016 73.8 0 4 1961 73.6 0 5 2007 73.0 0 6 2018 72.8 0 7 2021 72.7 0 8 2010 72.5 0 - 1959 72.5 0 9 2019 72.1 0 10 1998 71.6 0 11 2017 71.5 0 12 2023 71.3 1 - 2002 71.3 0 13 2020 71.1 0 14 2022 70.9 0 15 1971 70.8 0 16 2012 70.7 0 - 2011 70.7 0 - 2004 70.7 0 - 1985 70.7 0 17 1983 70.6 0 - 1968 70.6 0 18 2014 70.4 0 - 2008 70.4 0 - 1980 70.4 0 - 1970 70.4 0 - 1941 70.4 0 19 1965 70.3 0 - 1953 70.3 0 - 1945 70.3 0 20 1999 70.2 0 - 1957 70.2 0 21 1952 70.1 0 - 1946 70.1 0

9.06” at Valley Stream is one of the heaviest events of all-time for Western Nassau. Nassau County... Valley Stream 9.06 in 0906 PM 09/29 CWOP

Wettest September on record at JFK and 2nd wettest in NYC. Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 2023 12.79 1 2 1975 9.65 0 3 1960 9.60 0 4 2004 8.25 0 5 1966 7.47 0 6 2008 6.74 0 7 1999 6.73 0 8 1977 6.69 0 9 2018 5.99 0 10 1974 5.97 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Total Precipitation Missing Count 1 1882 16.85 0 2 2023 14.21 1 3 1934 11.96 0 4 2004 11.51 0 5 1944 10.30 0 6 1933 10.09 0 7 2021 10.03 0 8 2011 9.39 0 9 1975 9.32 0 10 1938 9.06 0

We can add July 2023 for our northern areas and September 2023 around NYC. Monthly Data for July 2023 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation NY WEST POINT COOP 18.12 CT WATERBURY 1.3 WNW CoCoRaHS 15.31 NY BEACON 4.2 ESE CoCoRaHS 14.21 NY SHRUB OAK COOP 12.96 NY PORT JERVIS 2.9 ESE CoCoRaHS 12.82 NY SOUTH SALEM 2.1 NW CoCoRaHS 12.60 NY THORNWOOD 0.7 NW CoCoRaHS 12.32 NY NEW HEMPSTEAD 0.6 SE CoCoRaHS 11.58 NY STONY POINT 0.7 NW CoCoRaHS 11.57 NY WALDEN 1.2 S CoCoRaHS 11.51 NY PORT JERVIS COOP 11.49 NY SOUTH SALEM 0.8 N CoCoRaHS 11.40 NY PEEKSKILL 0.4 N CoCoRaHS 11.37 CT EAST LYME 0.5 SW CoCoRaHS 10.97 NY CORNWALL ON HUDSON 0.6 NNW CoCoRaHS 10.91 CT SEYMOUR 1.2 WSW CoCoRaHS 10.86 CT NORTHFORD 0.8 SW CoCoRaHS 10.81 NY BRIARCLIFF MANOR 1.3 NE CoCoRaHS 10.76 NY MONTGOMERY ORANGE COUNTY AP WBAN 10.51 CT RIDGEFIELD 3.6 N CoCoRaHS 10.48 CT GUILFORD COOP 10.41 CT BROOKFIELD 3.3 SSE CoCoRaHS 10.38 CT ANSONIA 1 NE COOP 10.16 NY CARMEL 4N COOP 10.05 CT RIDGEFIELD 3.7 NNE CoCoRaHS 10.05 NY PINE BUSH 3.4 WSW CoCoRaHS 10.04 Monthly Data for September 2023 for Upton NY NWS CWA Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation NY NY CITY CENTRAL PARK WBAN 14.21 CT DANBURY MUNICIPAL AP WBAN 13.21 NY JFK INTERNATIONAL AIRPORT WBAN 12.79 NY LAGUARDIA AIRPORT WBAN 12.67 CT CROMWELL 0.4 WNW CoCoRaHS 12.40 CT PUTNAM LAKE COOP 11.56 CT PROSPECT 1.9 ENE CoCoRaHS 11.04 CT GRISWOLD 0.9 N CoCoRaHS 10.84 CT SEYMOUR 1.2 WSW CoCoRaHS 10.52 CT MIDDLEFIELD 0.6 SE CoCoRaHS 10.45 CT MERIDEN 2.8 WSW CoCoRaHS 10.45 NY WESTCHESTER CO AP WBAN 10.30 CT NORWICH 2.5 NNE CoCoRaHS 10.23

The PDO so out of phase with the ENSO is creating chaos with the short term PNA forecasts. So the models are struggling to get the Aleutian low position correct. A typical El Niño October has a very strong -EPO pattern. A La Niña -PDO has more of a +EPO in October. New run Old run October El Niño composite October -PDO La Niña composite

One of the strongest -PDO signatures that we have ever seen this time of year.

Pretty amazing radar loop.

First, the mean placement around NYC was spot on. Second, they have two maps. The ensemble mean was a little on the low side. And the max potential a little on high side. So highest amounts so far over 8” is a pretty good forecast when you blend the mean and max. Plus the radar estimates have been on the low side and there could be some areas that have close to 10.00”.

The HRRR and HREF did a fantastic job.

That’s the scary thing about flooding. The water will always find a way in. I can remember getting flooded out of my basement apartment in LB during the remnants of Agnes back in 72.

More photos of the very serious flooding in Brooklyn as some spots exceed 8 inches of rain.

Yeah, cars stalling out in the flooding there.