bluewave

June looks to a least start out similar to recent years. Ridge and warmth building to our west with a cool trough hanging on near New England. This has been a fairly consistent June pattern since the super El Niño in 2016.

Unusual to get a 590 DM ridge overhead in late May without low to mid 90s.

The ridge axis is pretty far north allowing more of an onshore flow for us. You can see how the warmer SW flow gets pushed up into NNE and SE Canada.

Early first 90 for portions of SE Canada and NNE. But a late one for us which usually occurs in May.

Yeah, NNE and Canada will reach 90 before we do this year.

7 days reaching 70 at Newark since April 1st is a new record low. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Number of Days Max Temperature >= 70 Apr 1 to May 24 Missing Count 1 2020-05-24 7 1 2 1967-05-24 9 0 - 1966-05-24 9 0 3 2003-05-24 12 0 - 1997-05-24 12 0 - 1978-05-24 12 0 - 1968-05-24 12 0 - 1950-05-24 12 0 - 1948-05-24 12 0 - 1940-05-24 12 0

This may be the first Memorial Day weekend that was warmer in portions of the Arctic than our area.

Euro still has no 90 degree days at Newark through the end of May. So it looks like the first time since 2014. First/Last Summary for NEWARK LIBERTY INTL AP, NJ Each section contains date and year of occurrence, value on that date. Click column heading to sort ascending, click again to sort descending. Year First Value Last Value Difference Minimum 04-07 (2010) 08-08 (2011) 69 Mean 05-21 09-12 113 Maximum 06-17 (2014) 10-02 (2019) 2019 05-26 (2019) 90 10-02 (2019) 96 128 2018 05-02 (2018) 90 09-06 (2018) 98 126 2017 05-17 (2017) 92 09-25 (2017) 90 130 2016 05-25 (2016) 91 09-23 (2016) 90 120 2015 05-25 (2015) 90 09-09 (2015) 91 106 2014 06-17 (2014) 91 09-06 (2014) 95 80 2013 05-30 (2013) 93 09-11 (2013) 96 103 2012 05-28 (2012) 91 09-07 (2012) 90 101 2011 05-30 (2011) 92 08-08 (2011) 93 69 2010 04-07 (2010) 92 09-25 (2010) 90 170

This will be one of the coolest Memorial Day weekends (Sat-Mon) since 2010 in NYC. It’s only the 3rd year with no 85+ high temperatures in Central Park. Memorial Day weekend(Sat-Mon) maximum high in NYC since 2010 2019...86 2018...89 2017...71 2016...92 2015...85 2014...86 2013...73 2012...89 2011...86 2010...86

These SST patterns can shift very quickly since they just respond to the surface and upper air patterns. So it usually comes down to what they do as we approach the peak of the hurricane season later on. But in the near term, the cooler SST’s and MJO will promote more of a trough pattern over the Northeast as we start a June. So the first 90 of the season will probably be late compared to recent years.

This year the cold pool extends further south down the coast than last year. It was mostly just east of New England at this time last year. Notice how much cooler the SST’s are off the entire East Coast now. This is a function of the much cooler April and May than last year. This year Last year Difference

It’s been a while since we had a cold pool off the coast in late May like this.

Looks like some cool 40s tonight on the strong NE flow.

Tail end of the slow moving cutoff that lead to those two dam failures in Michigan.

First inch+ heavy rain event here in SW Suffolk since mid-April.

Radar estimates of 2.50 inches of rain to the south of Jones Beach.

Some recent rainfall reports from NJ Somerset County... Somerville 1.73 in 0901 AM 05/23 CWOP Middlesex 1.63 in 0845 AM 05/23 IFLOWS Blackwells Mills 0.96 in 0905 AM 05/23 CWOP ...Sussex County... 0.7 NE Flatbrookville 1.22 in 0900 AM 05/23 HADS

So far a quick 1-2 inches of rain under the heaviest bands of training thunderstorms.

Radar estimates of 1.00 inch of rain in the last hour with the training thunderstorms near SMQ.

The new HRRR v4 has been doing pretty well this spring. It has areas that get 1-2” under the best banding. But areas outside the main bands will get less.

Euro has first 1-2” rain event since mid-April tonight into Saturday.

There had been a June cool pocket over the Northeast since the super El Niño in 2015-2016.

The last below normal AMJ was in 2003. 2020 39.1 40.1 48.0 50.4 57.2 M 2003 27.5 30.1 43.1 49.8 58.7 68.4

The MJO is only spending a brief period in the warm phases next week. So it quickly returns to the cooler 8-1 phases to start June. This is pretty much opposite of what happened from mid-December through March.

Cool onshore flow continuing into early next week. Then we transition to a warmer 80+ pattern away from the shore. The warm up is followed by the next cool down to start June.