donsutherland1

This was a rare—probably once-in-a-lifetime—event. That so much notable weather was occurring across the CONUS from a foot of snow in Seattle to the extreme Arctic outbreak/snow in Texas to the heavy lake effect-enhanced snow affecting parts of the Great Lakes Region makes this a very special period in terms of weather history.

IEMBot LOT @iembot_lot · 1h At 7:05 PM CST, 3 N Valparaiso [Porter Co, IN] TRAINED SPOTTER reports SNOW of 13.30 INCH. EVENT TOTAL AS OF 7:05 PM CST. UPDATES PREVIOUS SNOW TOTAL FROM 3 N VALPARAISO. https://mesonet.agron.iastate.edu/lsr/#LOT/202102160105/202102160105

Incredible capture.

More than likely, the SSW was the result of the blocking. Sometimes, SSW’s cause blocking. At other times, they occur in response to strong and persistent blocking, as happened during winter 2009-10.

Precipitation will move into the region this evening or overnight. Philadelphia, Newark, and New York City will likely see mainly rain. Far north and west of those cities, a period of snow, sleet, and freezing rain is likely. An area running from northeastern Pennsylvania, across northwestern New Jersey, central New York State and extending across central New England could pick up 0.10"-0.25" freezing rain with some higher amounts. Upstate New York and northern New England will likely pick up a moderate snowfall (4" or more) with some higher amounts, especially across northern Vermont, northern New Hampshire and northern Maine. Precipitation amounts from New Philadelphia to Boston will generally average 0.50"-1.50". The heaviest amounts are likely to the north and west of those cities. Another storm could bring moderate to significant snow to parts of the Northeast on Thursday into Friday. This is the kind of storm that could have a swath of 3"-6" snows with locally higher amounts. Some accumulation is likely in Newark and New York City before a changeover to sleet and then rain takes place. Afterward, a pattern change will unfold as the Arctic Oscillation goes positive. Starting on or just after February 20, a period of warmer than normal temperatures is likely in the Middle Atlantic and southern New England areas. Today, many areas in the Plains States, including Texas, experienced a additional record and near record cold temperatures from what has been the coldest air mass in three decades in many parts of that region. Minimum temperatures through 7 pm EST included: Amarillo, TX: -11° (old record: -6°, 1895) ***Coldest since February 1, 1951*** Austin: 8° (old record: 20°, 1909) ***Coldest since December 23, 1989*** Broken Bow, NE: -37° (old record: -14°, 2007) Brownsville: 28° Corpus Christi: 17° (old record: 25°, 1895) ***Coldest since December 24, 1989*** Dallas: 4° (old record: 15°, 1909) ***Coldest since December 23, 1989*** Denver: -16° Galveston: 21° (old record: 24°, 1909) Houston: 16° (old record: 18°, 1905) ***Coldest since December 24, 1989*** Kansas City: -10° (old record: -6°, 1936) Lincoln, NE: -16° (old record: -11°, 1978) Lubbock, TX: 0° (old record: 8°, 1951) ***Coldest since December 23, 1989*** North Platte, NE: -29° (old record: -23°, 1881) ***Coldest since December 22, 1989*** Oklahoma City: -6° (old record: 7°, 1909) Omaha: -15° (old record: -12°, 1936) Ord, NE: -35° (old record: -14°, 2007) Shreveport: 16° (old record: 21°, 1905) Tulsa: -3° (old record: 3°, 1905) Whitehorse, YT: -32° (old record: -31°, 1954) Record low maximum temperatures included: Austin: 25° (old record: 38°, 1909) Corpus Christi: 31° (old record: 33°, 1895) Dallas: 14° (old record: 31°, 1909) ***Coldest since December 22, 1989*** Houston: 25° (old record: 32°, 1909) Lincoln, NE: -4° (old record: -1°, 1936)***Coldest since February 2, 1996*** Lubbock, TX: 14° (old record: 30°, 1978) Oklahoma City: 4° (old record: 17°, 1909) ***Coldest since December 22, 1989*** Omaha: -3° (old record: -1°, 1936) ***Coldest since February 2, 1996) Tulsa: 5° (old record: 17°, 1909) ***Coldest since December 24, 1983*** Additional records are likely through tomorrow morning. Dallas will likely see temperatures fall to the single digits and likely the coldest levels on record so late in the season tomorrow morning. Select Record Low Minimum Temperatures for February 16: Amarillo: -4°, 1895 Austin: 20°, 1903 Brownsville: 22°, 1895 Corpus Christi: 20°, 1895 Dallas: 12°, 1903 Galveston: 19°, 1895 Houston: 13°, 1895 Lubbock: 13°, 1979 Tomorrow, Dallas could tie the record for most consecutive days with minimum temperatures below 10°. The record of three consecutive days was set during January 11-13, 1912 when the temperature fell to 9°, 1°, and 7° respectively. Records for the Dallas-Fort Worth area go back to September 1898. The Arctic Oscillation (AO) is rocketing from its lowest levels in nearly eight years. The latest guidance suggests that the AO will likely reach positive values as early as tomorrow. The last time the AO was positive was December 25, 2020 when the AO was +0.226. Whether this development will mark the end of the prolonged period of blocking that has prevailed throughout winter 2020-21 or a temporary break, remains to be seen. A dramatic increase in the AO has sometimes coincided with storminess. Therefore, the February 14-24 period might offer a window of opportunity for a meaningful storm. That window of opportunity could extend through the end of February should blocking persist or return. Since 1950, there were 11 cases during the January 16-February 28 timeframe that saw the AO rise at least 3 sigma from a minimum value of -4.000 or below within a 7-day period. Four cases saw a major snowstorm in parts of the Middle Atlantic or New England regions within 3 weeks of the AO's reaching its minimum value. The dates of the AO's minimum value for those four cases with storm dates in parentheses are January 25, 1958 (February 14-17, 1958 NESIS: 6.25), January 19, 1969 (February 8-10, 1969 NESIS: 3.51), February 15, 1969 (February 22-28, 1969 NESIS: 4.29), and January 16, 2016 (January 22-24, 2016 NESIS: 7.66). The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +6.72 today. The preliminary Arctic Oscillation (AO) figure was -0.389 today On February 14 the MJO was in Phase 7 at an amplitude of 2.880 (RMM). The February 13-adjusted amplitude was 2.725. Based on the latest guidance, no significant stratospheric warming event is likely into the closing days of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 23.3" snow. Winters that saw December receive 10" or more snow, less than 10" in January, and then 10" or more in February, saw measurable snowfall in March or April in 83% of cases. Winter 2009-2010 was the exception where only a trace of snow was recorded. This group of winters saw 6" or more snow during the March-April period in 50% of the cases. All said, it is more likely than not that there will be measurable snowfall after February. Based on sensitivity analysis applied to the latest guidance, there is an implied 81% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 33.0° (2.3° below normal).

Probably in 1895 and/or 1899, but I am not aware of documentation.

Morning thoughts... A record cold air mass moved into Texas yesterday producing widespread snow. Snowfall amounts included: Amarillo: 4.1”; Austin: 1.0”; Dallas: 4.0” (old record: 3.0”, 1951); and, Lubbock: 1.6”. Widespread record cold was present this morning. In the Pacific Northwest, the three-day snowstorm came to an end in Seattle with rain. The final accumulation was 12.4”,. At 8:40 am, some patches of freezing rain moving across southeast New York State. It will be mostly cloudy with some pockets of freezing drizzle and drizzle. Steadier precipitation will begin moving into the region this afternoon or this evening. An area running east-northeastward from northeast Pennsylvania to central New England will likely pick up 0.25”-0.50” freezing rain with locally higher amounts. A general 0.50”-1.50” precipitation is likely from Philadelphia to Boston. Temperatures will likely top out in the middle 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 37° Newark: 36° Philadelphia: 38° Precipitation will end tomorrow and it will be noticeably milder for a time in parts of the region. In the long-range, there reasonable consensus among the ensembles that a sustained milder pattern will develop around or just after February 20.

At 8 pm MST, the temperature in Denver had fallen to -13°. That breaks the previous daily record low temperature of -10°, which was set in 1903.

Tomorrow will see some patches of light freezing rain or freezing drizzle in the morning before a storm spreads precipitation into the region during the afternoon or evening. Philadelphia, Newark, and New Jersey will likely see mainly rain. Well north and west of those cities, a period of snow, sleet, and freezing rain is likely. An area running from northeastern Pennsylvania, across northwestern New Jersey, central New York State and extending across central New England could pick up 0.25"-0.50" freezing rain with some higher amounts. Upstate New York and northern New England will likely pick up a moderate snowfall (4" or more). Precipitation amounts from Philadelphia to Boston will generally average 0.50"-1.50". The heaviest amounts are likely to the north and west of those cities. Another storm could bring moderate to significant snow to parts of central and upstate New York into central and northern New England on Thursday into Friday. There could be some accumulation even in Newark and New York City before a changeover to sleet and then rain takes place. Afterward, a change in the pattern will unfold as the Arctic Oscillation goes positive. On or just after February 20, a period of warmer than normal temperatures is likely in the Middle Atlantic and southern New England areas. Parts of Canada and the Plains States, including Texas, experienced a continuation of record and near record cold temperatures from what has been the coldest air mass since December 1989 and February 1994 in parts of that region. Minimum temperatures through 6 pm EST included: Amarillo, TX: -1° Casper: -20° (old record: -14°, 2010) Dallas: 13° (old record: 15°, 1905, 1909, and 1936) Denver: -10° (tied record set in 1903) Lubbock, TX: 5° (old record: 12°, 2004) Norway House, MB: -37° (old record: -31°, 2008) Winnipeg: -31° Record low maximum temperatures included: Amarillo: 8° (old record: 12°, 1895) Austin: 30° (old record: 33°, 1951) Brownsville: 41° (old record: 44°, 1951) Chicago: 4° (old record: 8°, 1879 and 1943) Dallas: 22° (old record: 27°, 1951) Kansas City: 4° (old record: 7°, 1936) Lubbock, TX: 14° (old record: 25°, 2007) ***Tied February Record set on February 2, 2011*** Oklahoma City: 12° (old record: 20°, 1951) San Antonio: 30° (tied record set in 1895) St. Louis: 8° (old record: 19°, 1875 and 1943) Additional records are likely through Tuesday morning. Dallas will likely see temperatures fall to the single digits and likely the coldest levels on record so late in the season tomorrow morning. On Monday, the high temperature at Dallas could also challenge that city's record for the lowest maximum temperature on record. That record is 12°, which was set on February 12, 1899. Select Record Low Maximum Temperatures for February 15: Amarillo: 6°, 1895 Austin: 38°, 1909 Brownsville: 50°, 2007 Corpus Christi: 33°, 1895 Dallas: 31°, 1909 Houston: 32°, 1909 Lubbock: 30°, 1978 Select Record Low Minimum Temperatures for February 15: Amarillo: -6°, 1895 Austin: 20°, 1909 Brownsville: 25°, 1895 Corpus Christi: 25°, 1895 Dallas: 15°, 1909 Houston: 18°, 1905 Lubbock: 8°, 1951 The Arctic Oscillation (AO) is now rebounding from its lowest levels in nearly eight years. It is forecast to rise sharply in coming days. The latest guidance suggests that the AO will likely reach positive values for the first time since December 25, 2020 when the AO was +0.226. Whether this development will mark the end of the prolonged period of blocking that has prevailed throughout winter 2020-21, or a temporary break, remains to be seen. A dramatic increase in the AO has sometimes coincided with storminess. Therefore, the February 14-24 period might offer a window of opportunity for a meaningful storm. That window of opportunity could extend through the end of February should blocking persist or return. Since 1950, there were 11 cases during the January 16-February 28 timeframe that saw the AO rise at least 3 sigma from a minimum value of -4.000 or below within a 7-day period. Four cases saw a major snowstorm in parts of the Middle Atlantic or New England regions within 3 weeks of the AO's reaching its minimum value. The dates of the AO's minimum value for those four cases with storm dates in parentheses are January 25, 1958 (February 14-17, 1958 NESIS: 6.25), January 19, 1969 (February 8-10, 1969 NESIS: 3.51), February 15, 1969 (February 22-28, 1969 NESIS: 4.29), and January 16, 2016 (January 22-24, 2016 NESIS: 7.66). The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +5.00 today. The preliminary Arctic Oscillation (AO) figure was -2.131 today On February 13 the MJO was in Phase 7 at an amplitude of 2.724 (RMM). The February 12-adjusted amplitude was 2.611. Based on the latest guidance, no significant stratospheric warming event is likely through the end of the third week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 23.3" snow. Winters that saw December receive 10" or more snow, less than 10" in January, and then 10" or more in February, saw measurable snowfall in March or April in 83% of cases. Winter 2009-2010 was the exception where only a trace of snow was recorded. This group of winters saw 6" or more snow during the March-April period in 50% of the cases. All said, it is more likely than not that there will be measurable snowfall after February. Based on sensitivity analysis applied to the latest guidance, there is an implied 81% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.7° (2.6° below normal).

March 1969 snowfall amounts included: JFK: 3.5", LGA: 4.4", NYC: 5.6".

It’s here: https://www.americanwx.com/bb/topic/54543-feb-18-19-potential-1-2-qpf-into-the-snow-pack-possible-dangerous-icing-i84-corridor/

At 11 am CST, frigid air continued to push into Texas. Select temperatures: Amarillo: 0° (low so far: -1°) Dallas-Fort Worth: 17° Houston: 34° Lubbock: 6° (low so far: 5°; old record: 12°, 2004) The temperature in Houston will likely reach the teens tomorrow morning. The last time that happened was January 17, 2018 when the temperature fell to 19°. The last time before that was January 8, 1996 when the temperature also fell to 19°. Overall, Houston can expect its lowest temperature since December 24, 1989 when the mercury dipped to 11°. Select temperature levels and most recent occurrences: Amarillo: < 0°: February 14, 2021: -1° (through 11 am CST) < -1°: January 7, 2017: -3° < -3°: February 10, 2011: -6° < -6°: December 22, 1989: -8° < -8°: February 11, 1986: -12° < -12°: February 1, 1951: -14° Dallas-Fort Worth: < 16°: January 17, 2018: 13° < 13°: February 4, 1996: 8° < 8°: December 23, 1989: -1° Houston: < 20°: January 17, 2018: 19° < 19°: December 24, 1989: 11° Lubbock: < 10°: February 14, 2021: 5° (through 11 am CST) < 5°: January 1, 2018: 4° < 4°: February 2, 2011: 2° < 2°: December 23, 1989: -1° < -1°: December 22, 1989: -2° < -2°: January 5, 1971: -4° < -4°: January 13, 1963: -16°

I remember that heat very well.

The sample size is too small to draw conclusions. Below are the outcomes for the February cases where the AO reached -5.000 or below: February 1969: Blocking continued through much of March with 28 days on which the AO was negative and 23 days on which it was -1.000 or below: Minimum: -3.469, March 19. February 1978: Blocking effectively ended after the first week of March. Minimum: -3.217, March 4. February 2010: Blocking returned in late March. Minimum: -2.251, March 28. Winter 2009-10 saw only a trace of snow for the March-April 2010 period.

There was. Since 1950, there were 11 cases during the January 16-February 28 timeframe that saw the AO rise at least 3 sigma from a minimum value of -4.000 or below within a 7-day period. Four cases saw a major snowstorm in parts of the Middle Atlantic or New England regions within 3 weeks of the AO's reaching its minimum value. The dates of the AO's minimum value for those four cases with storm dates in parentheses are January 25, 1958 (February 14-17, 1958 NESIS: 6.25), January 19, 1969 (February 8-10, 1969 NESIS: 3.51), February 15, 1969 (February 22-28, 1969 NESIS: 4.29), and January 16, 2016 (January 22-24, 2016 NESIS: 7.66).

Morning thoughts... Record-cold is now advancing through Texas with falling temperatures and snow. At Dallas, the 6 am CST temperature was 18°. The daily record low maximum temperature of 27°, which was set in 1951, will very likely be broken today. The temperature will then plunge into the single digits tonight. In the Pacific Northwest, Seattle picked up 8.9” snow yesterday. That was Seattle’s biggest daily snowfall since January 27, 1969 when 14.9” snow fell and its 12th biggest daily snowfall on record, tied with December 23, 1965. The daily record for February 13 was 1.1” from 1986. In the northern Middle Atlantic and southern New England regions, much quieter weather will prevail today. It will be mostly cloudy with some pockets of freezing drizzle and drizzle. Temperatures will likely top out in the middle 30s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 36° Newark: 36° Philadelphia: 37° Tomorrow will likely see precipitation overspread the area. In the long-range, there is growing consensus among the ensembles that a sustained milder pattern will develop around or just after February 20.

Light freezing rain has commenced in Larchmont, NY. A few sleet pellets are mixed in.

Beyond two weeks, predictability of the AO is not great. And it’s just one variable in the mix.

A period of light precipitation is likely tonight into tomorrow. Little or no snow accumulation (0.5" or less) is likely in Philadelphia, Newark, and New York City. Some freezing rain is possible, with larger amounts north and west of those cities. Additional storms will very likely impact the region next week. Parts of the Northern Plains and Canada experienced a continuation of record and near record cold temperatures from what has been the coldest air mass since February 1994 in parts of that region. Minimum temperatures included: Duluth: -35° (old record: -29°, 1905) ***Coldest since February 2, 1996*** Estevan, SK: -37° (old record: -31°, 1970) Flin Flon, MB: -44° (old record: -38°, 1974) International Falls, MN: -42° (old record: -39°, 1909) Norway House, MB: -48° (old record: -38°, 2008) Prince Albert, SK: -43° (old record: -41°, 1951) Regina: -37° Saskatoon: -34° The Pas, MB: -43° (old record: -34°, 2008) Thompson, MB: -46° (old record: -45°, 2014) Winnipeg: -36° (old record: -34°, 1949) That frigid air will continue to slowly advance south and eastward through the remainder of this weekend. This will lead to snow and record-breaking cold in Texas. Select Record Low Maximum Temperatures for February 14: Austin: 33°, 1951 Brownsville: 44°, 1951 Corpus Christi: 30°, 1895 Dallas: 27°, 1951 Select Record Low Minimum Temperatures for February 14: Austin: 10°, 1899 Brownsville: 18°, 1899 Corpus Christi: 26°, 1895 Dallas: 15°, 1905, 1909, 1936 Select Snowfall Records for February 14: Austin: 1.6", 2004 Dallas: 3.0", 1951 Dallas will likely see temperatures fall to the single digits and likely the coldest levels on record so late in the season. On Monday, the high temperature at Dallas could also challenge that city's record for the lowest maximum temperature on record. That record is 12°, which was set on February 12, 1899.However, this air mass will likely avoid any direct impact on the Middle Atlantic and New England areas. A piece of the air mass could still graze the region at some point next week. The Arctic Oscillation (AO) is now rebounding from its lowest levels in nearly eight years. It is forecast to rise sharply in coming days. The latest guidance suggests that the AO could attain positive values for the first time since December 25, 2020 when the AO was +0.226. This development will likely lead to at least a period of above normal temperatures in the East. Whether it will mark the end of the prolonged period of blocking that has prevailed throughout winter 2020-21, or a temporary break, remains to be seen. A dramatic increase in the AO has sometimes coincided with storminess. Therefore, the February 14-24 period might offer a window of opportunity for a meaningful storm. That window of opportunity could extend through the end of February should blocking persist or return. Since 1950, there were 11 cases during the January 16-February 28 timeframe that saw the AO rise at least 3 sigma from a minimum value of -4.000 or below within a 7-day period. Four cases saw a major snowstorm in parts of the Middle Atlantic or New England regions within 3 weeks of the AO's reaching its minimum value. The dates of the AO's minimum value for those four cases with storm dates in parentheses are January 25, 1958 (February 14-17, 1958 NESIS: 6.25), January 19, 1969 (February 8-10, 1969 NESIS: 3.51), February 15, 1969 (February 22-28, 1969 NESIS: 4.29), and January 16, 2016 (January 22-24, 2016 NESIS: 7.66). The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.7°C for the week centered around February 3. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail at least through meteorological winter. The SOI was +2.69 today. The preliminary Arctic Oscillation (AO) figure was -3.177 today On February 12 the MJO was in Phase 7 at an amplitude of 2.610 (RMM). The February 11-adjusted amplitude was 2.131. Based on the latest guidance, no significant stratospheric warming event is likely through the end of the third week of February. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 23.3" snow. Winters that saw December receive 10" or more snow, less than 10" in January, and then 10" or more in February, saw measurable snowfall in March or April in 83% of cases. Winter 2009-2010 was the exception where only a trace of snow was recorded. This group of winters saw 6" or more snow during the March-April period in 50% of the cases. All said, it is more likely than not that there will be measurable snowfall after February. Based on sensitivity analysis applied to the latest guidance, there is an implied 83% probability that New York City will have a colder than normal February. February will likely finish with a mean temperature near 32.4° (2.9° below normal).

It depends on how much predictability one is looking for. The statistical evidence is fairly clear that snowfall is more frequent during negative AO states in the New York City area (and also Middle Atlantic Region). For all days in December, January, February, and March from January 1, 1950 through January 31, 2021, there were 4,628 days (53.6% days) when the AO was negative, including 2,945 (34.1% days) when it was -1.000 or below. There were 4,008 days (46.4% days) when the AO was positive, including 2,337 days (27.0% days) with values of +1.000 or above. On three days, the AO was 0.000. Below is the share of total January-March and December snowfall for New York City: AO of -1.000 or below: 41.9% of snowfall (34.1% days): Overrepresented AO-: 61.6% of snowfall (53.6% days): Overrepresented AO+: 38.4% of snowfall (46.4% days): Underrepresented AO of +1.000 or above: 20.1% of snowfall (27.0% days): Underrepresented. In addition, days with measurable snowfall were 28% more frequent when the AO was negative than when it was positive and 42% more frequent at values of -1.000 or below than when it was positive. In terms of daily snowfall of 4" or more, those outcomes were 48% more frequent when the AO was negative than when it was positive and 58% more frequent when the AO was -1.000 or below than when it was positive. If one compares AO cases of -1.000 or below vs. AO cases of +1.000 or above, days with measurable snowfall and days with 4" or more snowfall were 43% and 75% more frequent respectively. For a more recent illustration, for the last five February cases (through February 13, 2021), there were 31 days (31.6% days) during which the AO was negative and 67 days (68.4% days) when it was positive. During the AO- days, there was 25.6" snow (89.2% snow) and 3.1" snow (10.8% snow) when the AO was positive. Even excluding February 2021 on account of the big storm, 58.7% of the snow was recorded during the 21.1% of days when the AO was negative while 41.3% of the snowfall was recorded during the 78.9% of days when the AO was positive. In short, a negative AO, especially one at -1.000 or below, provides a favorable large-scale state for snowfall overall in the Middle Atlantic Region. However, the synoptic details matter. The placement of synoptic features and their evolution occur within the large-scale hemispheric background state and are, at least in part, influenced by the AO.

That’s why I did not cite it. On one day,(2/24), ISP was shown to have received 11.0” snow on 0.11” precipitation. The correct figure almost certainly is 1.1”, as snow cover rose from 0” to 1”.

A due north wind spends more time over the Long Island Sound for JFK than it does for LGA.

March 29.

Mostly rain. NYC saw 1.3”, JFK received 1.6”, and LGA picked up 2.0”.