bluewave

Continuation of the less warm is the new cool pattern for us. Newark was +0.4 in August and +0.3 through the first 12 days of September. With the exception of July, the strongest heat this warm season has missed to our south and west. This is how DCA is ahead of EWR by 30 days of 90 or greater. It’s a first for the 2010’s. The normal amount is 9 to 21 days. 90 degree days at DCA and EWR ..........DCA....EWR....difference 2019....55...25....+30 2018....45...36.....+9 2017....43...22....+21 2016....58...40....+18 2015....52....35....+17 2014...24....15.....+9 2013...35.....25.....+10 2012...53.....33......+20 2011....50.....31.....+19 2010....67.....54......+13 10 day forecast temperature departure higher to our south and west

Our climate has been becoming a much wetter one. That 80 inch amount may be a bit overdone with the rain gauge problem in 1983. But White Plains picked up 74.15, so it may not be that far off.

Same old story since late July with the record heat remaining to our south. Looks like Atlantic City tied their record high of 94 degrees. Less warm is the new cool for us. 9/12 94 in 1961 91 in 1952 89 in 2005+

That was a very impressive US drought in the early to mid 50’s. Most of our higher count 100 degree day years had extensive drought in the Central or Eastern US. We briefly got into this geographic severe drought regime from 2010-2013. Newark was able to set the all-time record high of 108 during the historic Southern Plains drought in 2011.This pattern reversed in the following years with the record rainfall, more clouds, and record dewpoints limiting 100 degree potential.

The latest 90 at JFK was 10-8-07 with the 2nd on 9-24-17. The latest 100 was 8-27-48 with 8-20-83 coming in 2nd. But it’s possible 9-2-53 was last 100 since the JFK data is missing for that month. 1953 still stands as our greatest late season heatwave. One of the few heat records that the 2010’s couldn’t beat. Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature 1953-08-24 90 1953-08-25 93 1953-08-26 91 1953-08-27 93 1953-08-28 100 1953-08-29 100 1953-08-30 100 1953-08-31 102 1953-09-01 96 1953-09-02 105 1953-09-03 94

NSIDC extent continues to bounce up and down with the rapidly changing dipole conditions. 9-4......4.238 million sq km......lowest of season so far 9-9......4.342...... a 5 day increase of +104k 9-11.....4.280........a 2 day decline of -62k

The Atlantic tropics may stay active right into October with such a favorable MJO VP signature.

JFK is on track for the 6th earliest last 90 degree day. #1...6-9-04 #2...7-8-86 #3...7-15-92 #4...7-16-94 #5...7-20-13 #6...7-21-19....so far

The most impressive heat last fall was front-loaded into the first week of September. Data for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Date Max Temperature Min Temperature Avg Temperature Avg Temperature Departure 2018-09-01 78 70 74.0 0.8 2018-09-02 82 68 75.0 2.1 2018-09-03 95 76 85.5 12.9 2018-09-04 95 78 86.5 14.2 2018-09-05 91 78 84.5 12.4 2018-09-06 98 76 87.0 15.2 2018-09-07 79 71 75.0 3.6

Highs into the 80’s and above during the 2nd half of September have been fairly typical this decade. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Ending Date Highest Max Temperature Sep 15 to Sep 30 Missing Count 2018-09-30 84 0 2017-09-30 92 0 2016-09-30 90 0 2015-09-30 89 0 2014-09-30 87 0 2013-09-30 80 0 2012-09-30 79 0 2011-09-30 82 0 2010-09-30 90 0

Continuing with the brief warm up followed by big Canadian high theme. The high behind the backdoor cold front will approach peak intensity for this time of year.

Thursday looks like an impressive backdoor cold front for this time of year after the brief warm up. 50’s to our north with 90’s down around DC. Coastal sections could see NE gusts in the 30 to 40 mph range with such strong high pressure over New England.

Still on track for a brief warm up next few days as the warm spots may approach 90. But followed by another cool down with the next big Canadian high. What a difference a year makes as Newark reached 98 last September. That was the 4th highest September maximum temperature at Newark. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Sep Click column heading to sort ascending, click again to sort descending. Year Highest Max Temperature Missing Count 2019 90 21 2018 98 0 2017 92 0 2016 94 0 2015 98 0 2014 95 0 2013 96 0 2012 92 0 2011 88 0 2010 98 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Sep Click column heading to sort ascending, click again to sort descending. Rank Year Highest Max Temperature Missing Count 1 1953 105 0 2 1993 100 0 3 1983 99 0 4 2018 98 0 - 2015 98 0 - 2010 98 0 - 1980 98 0

We probably have to wait until October for the first clues. Last October we saw the dramatic SOI reversal and more Niña-like SST state west of the dateline. We’ll get to see if the current more Niño looking pattern can hold through this October. SOI currently continues negative with a developing WWB west of the dateline and most positive IOD since 2015.

Same old story this week. Brief warm up followed by another big Canadian high to cool things off again.

There were 2 new monthly record low average NSIDC extents in 2019. The records occurred in April and July. There have been 9 new monthly records since 2016. ASO are the only 3 months without a new monthly record low average extent since 2016. https://mobile.twitter.com/ZLabe/status/1157122835409596416 NSIDC monthly record lowest average sea ice extents Jan...2018 Feb.. 2018 Mar...2017 Apr....2019 May...2016 Jun....2016 Jul.....2019 Aug...2012 Sep...2012 Oct...2012 Nov...2016 Dec...2016

Yeah, I would rather take my chances with a coupled El Niño type atmospheric state next winter than what we had last winter. While the sample simple size of dud winters since 2003 is small, they all had some really bad Niña-like features.

It’s like a weird atmospheric delayed response to the El Niño. Last fall and winter seemed to be stuck in more of a La Niña-like state despite the El Niño. Now we have the strongest +IOD since 2015-2016 combined with the -SOI. Pretty good developing WWB pattern now near the dateline. Check out how much the summer matched up with the typical El Niño 500 mb pattern.

The term behavior is commonly used when referring to sea ice. Odd would be a mild term for describing the first time pressure extremes that this season has exhibited. Those extremes lead to the unusual pattern of sea ice loss this melt season.

Odd late season behavior continues on NSIDC extent. Extent has increased 95k last 2 days. It was 4.238 million sq km on 9-4 and now 4.333 million sq km for the 6th. The melt season featured a record low extent for July only to fall back to 4th place as of 9-6. Big slowdown after mid August followed by an acceleration of losses into early September. Currently in 4th place for NSIDC extent. 3.387....2012-9-17 4.155....2007-9-18 4.165....2016-9-10 4.333....2019 4.344....2011-9-11  4.433....2015-9-9 4.586....2008-9-19  4.615....2010-9-21  4.656....2018-9-23  4.665....2017-9-13 Zack Labe notes the statistical tie for record Arctic warmth this summer with 2012. https://mobile.twitter.com/ZLabe/status/1170022132216029185 Boreal summer 2-m temperatures were statistically tied (with 2012) for the warmest on record in the #Arctic [using JRA-55 data]

Wednesday into Thursday looks like our next chance for 90 degree heat in the warm spots. There will probably be a sharp high temperature gradient around the region with the highest temperatures again near DC. The DC area experienced record heat a few days ago reaching 96 degrees. This was the first year during the 2010’s that DCA had so many more 90 degree days than EWR. But both locations will a shot to add to the list by midweek. 90 degree days at DCA and LGA ...........DCA..EWR...difference 2019....53...24....+29 2018...45....36.....+9 2017...43....22.....+21 2016...58....40.....+18 2015...52....35.....+17 2014...24....15......+9 2013...25.....35....+10 2012....53....33....+20 2011...50.....31.....+19 2010...67....54......+13

The first Dorian surfing photos from Long Beach getting posted on Instagram. Swells built very quickly last few hours.

Just had a very heavy downpour here in SW Suffolk with visibility down to 1/4 of a mile. Was heavier than indicated by radar.

Yeah, that looks like the next time that some 90 degree heat may try to sneak in again. Short warm ups between big Canadian highs has been the theme since the end of July. The trough digs into the West 9/10-9/11 and really pumps up the WAR.

NSIDC daily extent down another 48k to 4.238 million sq km. This was the largest drop from 8-29 to 9-4 going back to 2007. 8-29 to 9-4 Arctic sea ice decline 2019...-409k 2018...-130k 2017...-119k 2016...-248k 2015...-98k 2014...-174k 2013...-161k 2012...-146k 2011....-291k 2010....-266k 2009....-159k 2008.....-326k 2007.....-272k