bluewave

The Euro gets upgraded next week. Significant improvement in moist processes. This will eventually allow for 4-5km convection permitting resolutions in the future. It will be interesting to see what a global model looks like when run at resolutions like the HRRR and hi res NAM. Maybe this moist process upgrade next week will improve the east coast storm track suppression issue that popped up with one of the upgrades after 2013. We are pleased to confirm the operational implementation of IFS Cycle 47r3 with the 06 UTC run, 12 October 2021 The upgrade will bring improvements to the assimilation and observations usage and a significantly improved physical basis for moist processes, necessary to facilitate further development of the Integrated Forecasting System (IFS) and future application at convection-permitting resolutions. The release candidate phase has been running in near real-time since 14 September. In a recent Webinar we explained the scientific background, its meteorological impact, and some new and revised products. Forecast users are recommended to read "47r3 Impact on Surface Weather representation", highlighting the changes with 47r3 in the characteristics of many frequently used forecast fields and products. We would also like to remind you of a change to the “Master Tables Version Number”, affecting allparameters in GRIB 2, and encourage you to check your data processing with the test data provided as soon as possible ahead of implementation. Detailed information can be found on the 47r3 implementation page. Please “watch” the page to get notified about further updates. https://confluence.ecmwf.int/display/FCST/47r3+Impact+on+Surface+Weather+representation IFS cycle 47r3 is delivering noteworthy changes in the characteristics of many of the forecast fields (such as precipitation) and forecast products regularly used by forecasters and others. These changes are probably more substantial, as a whole, than anything we have seen with any ECMWF cycle in the last 10 years. This page aims to highlight the key differences. It is common forecaster practice to adjust for perceived/known biases or weaknesses in model behaviour, and given the new characteristics application of these ("old") corrections to output from the new cycle may no longer be appropriate. Some such corrections can be discarded or toned down; other new ones may need to be introduced. Most of the changes with 47r3 are attributable to the new "Moist Physics" package, affecting cloud and precipitation in particular. However changes to the visibility and gust diagnostics will also have a substantial impact on occasion. Impacts are listed below, by parameter, with examples generally comparing output from cycle 47r2 (operational until 12 October 2021) and contiguous non-operational runs of 47r3 (operational from 12 October 2021). Unless stated otherwise examples are from HRES. "NEW CYCLE" on plots below means 47r3.

Multiyear ice finishes at 2nd lowest on record with extent in 12th place.

The latest extreme rainfall event.

International Falls is headed for the latest first freeze on record as much of North America has well above average temperatures. Frost/Freeze Summary for International Falls Area, MN (ThreadEx) Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year Last Value First Value Season Length 2016 06-08 (2016) 30 10-08 (2016) 29 121 1919 05-08 (1919) 32 10-06 (1919) 25 150 1988 05-14 (1988) 31 10-04 (1988) 25 142 1968 05-23 (1968) 30 10-04 (1968) 27 133 1921 06-04 (1921) 29 10-03 (1921) 31 120 2017 05-24 (2017) 30 09-29 (2017) 32 127 1994 05-10 (1994) 26 09-29 (1994) 32 141 1920 05-13 (1920) 29 09-29 (1920) 28 138 2019 06-02 (2019) 29 09-28 (2019) 29 117 2015 06-01 (2015) 30 09-28 (2015) 28 118 Euro October forecast

Looks like the high was 68° with the minimum driving the warm departure.

It’s interesting how close that Pacific forecast is to DJF 16-17 and 17-18. While we had the background SE Ridge, the Aleutian ridge built over the top at times for -AO periods. So getting those blocking intervals will be essential for near to above normal snowfall this winter. DJF 2016-2017 and 2017-2018

The Euro seasonal just came out today. It’s really hitting the Aleutians Ridge very hard. So if that is correct, then we will need blocking to have a shot at above normal snowfall. While we had a strong SE Ridge in 16-17 and 17-18, blocking intervals gave us above normal snowfall to go with the above normal temperatures.

At least for our area, there really isn’t much correlation between ENSO and snowfall. Snowfall amounts come down to how much blocking we get. Above normal snowfall and above normal temperatures has been the most common winter combination in our area since 2002-2003. That was the year the record snowfall and -AO/-NAO blocking patterns become more frequent. Above normal snowfall and above normal temperatures 7 years 20-21 17-18 16-17 15-16 12-13 05-06 04-05 Above normal snowfall and below normal temperatures 6 years 14-15 13-14 10-11 09-10 03-04 02-03 Below normal snowfall and above normal temperatures 5 years 19-20 18-19 11-12 07-08 06-07 Near normal temperatures and near normal snowfall 1 year 08-09

This fall is featuring the strongest -PDO pattern in years. It results in a warmer than average +EPO/-PNA pattern with a pumped up SE Ridge. Main question for the winter is will we get enough blocking to tame this pattern a bit? Second winters after extreme blocking like last year usually had follow up blocking.

Today was one of the easterly flow days that I mentioned yesterday when the warm minimums drive the departure. The high at JFK was +4 and the low so far of 67° is +13°. So the low could fall a few more degrees before midnight and still be close to +10°. CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 433 PM EDT MON OCT 04 2021 ................................... ...THE KENNEDY NY CLIMATE SUMMARY FOR OCTOBER 4 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1948 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 73 940 AM 84 1967 69 4 69 MINIMUM 67 214 AM 39 1996 54 13 47 AVERAGE 70 62 8 58

The latest extended EPS continues the warmer than average temperatures during the next few weeks. The deep trough digging into the West will keep pumping SE Ridge. Oct 4-11 Oct 11-18

Low 80s in the warm sector over Central NJ. Wrightstown MOSUNNY 81 66 59 S3

The 68° dew point at 7 am in October is just a few degrees off the record of 71° set back in 2018. https://forecast.weather.gov/product.php?site=NWS&issuedby=OKX&product=RWR&format=CI&version=1&glossary=1&highlight=off

Today is a preview of the next few weeks. Days when we get SW flow the maximum departures will dominate. When the flow turns more easterly with clouds and rain, then the warm minimums will drive the daily warm departures. There may be several days in the mix when the warm maxes and mins can equally dominate. Albany with the easterly flow warm +10 minimum CLIMATE REPORT NATIONAL WEATHER SERVICE ALBANY NY 432 PM EDT SUN OCT 03 2021 ................................... ...THE ALBANY NY CLIMATE SUMMARY FOR OCTOBER 3 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD: 1991 TO 2020 CLIMATE RECORD PERIOD: 1874 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 65 2:59 PM 83 1922 67 -2 58 1967 MINIMUM 56 3:34 AM 29 1945 46 10 37 AVERAGE 61 56 5 48 SW flow in our area with the +8 to +13 maximums driving the warm departures CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 435 PM EDT SUN OCT 03 2021 ................................... ...THE NEWARK NJ CLIMATE SUMMARY FOR OCTOBER 3 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1931 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 84 102 PM 85 1950 71 13 69 MINIMUM 56 553 AM 37 1945 54 2 48 AVERAGE 70 62 8 59 CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 435 PM EDT SUN OCT 03 2021 ................................... ...THE LAGUARDIA NY CLIMATE SUMMARY FOR OCTOBER 3 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1939 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 81 212 PM 85 2000 71 10 69 MINIMUM 63 640 AM 40 1974 58 5 55 AVERAGE 72 64 8 62 CLIMATE REPORT NATIONAL WEATHER SERVICE NEW YORK, NY 435 PM EDT SUN OCT 03 2021 ................................... ...THE ISLIP NY CLIMATE SUMMARY FOR OCTOBER 3 2021... VALID TODAY AS OF 0400 PM LOCAL TIME. CLIMATE NORMAL PERIOD 1991 TO 2020 CLIMATE RECORD PERIOD 1963 TO 2021 WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST VALUE (LST) VALUE VALUE FROM YEAR NORMAL ................................................................... TEMPERATURE (F) TODAY MAXIMUM 77 1214 PM 80 2000 69 8 68 2002 MINIMUM 56 540 AM 34 2003 52 4 48 AVERAGE 67 60 7 58

JFK needs 4 more days to tie the record set in 2010. Time Series Summary for JFK INTERNATIONAL AIRPORT, NY - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Max Temperature >= 75 Missing Count 2010 124 0 2001 124 0 1971 124 0 2015 123 0 2016 121 0 2005 121 0 1991 120 0 1963 120 0 2021 120 89 2012 119 0 2007 119 0

Another 75° at Islip brings them to within one day of the all-time record. Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Jan through Dec Click column heading to sort ascending, click again to sort descending. Rank Year Number of Days Max Temperature >= 75 Missing Count 2007 120 0 1991 120 0 2021 119 89 2010 118 0 2011 117 0 2005 116 0 2001 116 0 2016 115 0 2015 115 0 2018 114 0 2017 113 0 2020 112 0 2014 112 0 1980 112 0 1998 111 0 2013 110 0

We haven’t had a cold October since 2009.

Continuation of the extended warmth theme following brief periods of slightly cooler than normal temperatures. Our last -10 departure day was way back on the July 4th weekend. The coldest departure of the whole year so far was during the Memorial Day weekend. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=32&network=NYCLIMATE&station=NYC004&year=2021&var=avg&gddbase=50&gddceil=86&how=diff&cmap=jet&dpi=100&_fmt=png

The minimum at NYC was lower than EWR and LGA. But you can see the deep shade shaving at least 3°off the high temperature. The high temperature on the Great Lawn in Central Park was probably around 70°instead of 67° in the deep shade near the castle. LGA………….…....70/54 NYC………………..67/51 JFK………………...70/50 EWR………………..72/52 FRG…………………68/49 ISP………..……...…68/49 Brownsville …….73/54 Ozone Park……..71/52

October has been one of our fastest rising temperature months of the fall along with September. The area just experienced the warmest October on record back in 2017. The highest monthly maximum temperature record was set in 2019 with the flash drought and mid 90s. It’s also interesting that most 60° Octobers have been La Ninas. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Oct Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature ENSO 2017 63.8 La Niña 2007 63.5 La Niña 1971 63.1 La Niña 1990 62.4 Neutral 1984 62.2 La Niña 1949 61.6 La Niña 1963 61.2 El Niño 1995 61.0 La Niña 1947 61.0 Neutral 2019 60.4 Neutral 1954 60.4 La Niña 1973 60.3 La Niña 1946 60.0 El Niño

With how warm it has been, the -2.7 average departure felt much cooler today. 6 station average..-2.7 EWR…..-1 NYC…..-5 LGA……-3 JFK……-3 ISP…….-2 BDR……-2

The 70° at Newark yesterday and today is in line with the warmer spots in the 5 Boroughs of NYC. The NYC micronet is a great addition to our urban observations. Notice how there were several 70° highs yesterday. Ozone Park is currently at 70° this afternoon. https://www2.nysmesonet.org/networks/nyc 9-30 highs… Bensonhurst / Mapleton 70 Brownsville 70 Highs so far today Lefferts / South Ozone Park Temp: 70°F 3h Precip: 0.00″

Sure. It’s getting to the point that we need extreme blocking even for a brief cooldown. The nearly 5sd block over that part of Canada looks like a new record for this time of year. But it builds quickly southward and merges with the SE Ridge for a quick warm up. My guess is that the models continue this warmer ridge well into October since it’s part of the La Niña forcing pattern. But even for a La Niña pattern in October, this ridge is on the extreme side as we have been seeing with the 500 mb patterns.

It would be great if the NYC ASOS in Central Park got this type of attention to its accuracy. PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE ALBANY NY 752 AM EDT THU SEP 30 2021 ...PUBLIC INFORMATION STATEMENT... ...NATIONAL WEATHER SERVICE REPLACEMENT OF THERMOMETER AT ALBANY INTERNATIONAL AIRPORT... THE NATIONAL WEATHER SERVICE RECONDITIONING CENTER (NWSRC) REPLACED THE AUTOMATED SURFACE OBSERVING SYSTEM THERMOMETER AND ASSOCIATED ELECTRONICS AT THE ALBANY INTERNATIONAL AIRPORT YESTERDAY, SEPTEMBER 29, 2021 AT 9:30 AM. THE THERMOMETER WAS REPLACED WITH A MODIFIED SENSOR AND CALIBRATED WITH A MODIFIED ALIGNMENT PROCEDURE. A REFERENCE THERMOMETER, RUNNING SIDE BY SIDE WITH THE ASOS THERMOMETER, HAS COLLECTED DATA FOR COMPARISON SINCE JUNE. THE PREVIOUS THERMOMETERS INSTALLED SINCE JULY 17, 2020 LIKELY HAD A COLD BIAS (THERMOMETER RECORDS A COLDER TEMPERATURE THAN THE ACTUAL TEMPERATURE). THE NATIONAL WEATHER SERVICE WILL CONTINUE THE INVESTIGATION ON THE COLD BIAS IN THE ALBANY TEMPERATURE RECORD FOR THE PERIOD JULY 17, 2020 THROUGH SEPTEMBER 29, 2021. PLEASE CONTACT SUSAN BUCHANAN, DIRECTOR OF PUBLIC AFFAIRS, NATIONAL WEATHER SERVICE AT 301-427-9000 FOR ADDITIONAL INFORMATION. $$ 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.