June 2020 General Discussions & Observations Thread

[Brian5671]

Dwpoint down to 60 here as drier air filters in

[jm1220]

50 minutes ago, uofmiami said:

 

 

It’s comical how often this pattern repeats with either the cutoffs coming overhead or some trough digging northeast of us. Whenever models start hinting at it 7-8 days ahead you know what’s coming.

[Cfa]

3 hours ago, Cfa said:

Still humid in Long Island, currently 88/73 and alternating between sun and clouds.

Dew down to 58 now, temp is 89, high of 91.

[dWave]

Current temp 87 which is the high, dew down to 53.

[bluewave]

35 minutes ago, jm1220 said:

It’s comical how often this pattern repeats with either the cutoffs coming overhead or some trough digging northeast of us. Whenever models start hinting at it 7-8 days ahead you know what’s coming.

The blocking from Siberia to the Great Lakes almost looks like a cold season pattern.

[nycwinter]

lovely summer evening what a difference a day makes when the humidity is lower..

[bluewave]

Not quite. There were a number of extreme conditions about in 2019/2020 which perhaps point to a common driver in the Indian Ocean. In the fullness of time we may find a unifying explanation for the SH SSW, QBO disruption and record cold/strong NH PV.

 

Abstract

The quasi-biennial oscillation (QBO) is a repeating cycle of tropical stratosphere winds reversing direction from eastward to westward roughly every 14 months. Discovered independently by British and American scientists the QBO continued undisturbed for 27 cycles from 1953 until February 2016 when a westward jet unexpectedly formed in the lower stratosphere during the eastward phase. This disruption is attributed to unusually high wave momentum fluxes from the Northern Hemisphere. A second, similar, QBO disruption occurred during the 2019/2020 northern winter though this time the Arctic polar vortex was exceptionally strong and wave fluxes weak. Here we show that this latest disruption to the regular QBO cycling was twice as strong as that seen in 2016 and resulted from horizontal momentum transport from the Southern Hemisphere. The disruption began in September 2019 when there was a rare Southern Hemisphere sudden stratospheric warming followed by abnormal conditions in the stratosphere with the smallest ozone hole since its discovery and enhanced equatorward momentum fluxes. In both disruptions the normal downward progression of the QBO halts and the eastward shear zone above the disruption moves upward assisted by stronger tropical upwelling during the boreal winter. Results from the two disruptions provide compelling evidence of a fundamental change in our understanding of the dynamics of the QBO with extra-tropical influences more significant than previously thought. In turn, this implies a less predictable QBO. Furthermore, the expected climate response of the mechanism we have identified suggests that reoccurring QBO disruptions are consistent with an emerging signal of climate change weakening QBO amplitudes as predicted by models.

[LoboLeader1]

Currently 82 here, RH at a very comfortable 32%.

[doncat]

88° today with the lower humidity.

[donsutherland1]

A disturbance moved into northern New England and southern Canada this morning. As a result, morning clouds gave way to abundant afternoon sunshine. Temperatures again rose well into the 80s across the region.

Tomorrow will again see partial sunshine with readings in the lower and middle 80s across the area. A few areas could see some showers or thundershowers, but again many areas will remain dry.

Meanwhile, parts of northern and western Europe experienced record warmth today. Daily records included:

Alesund, Norway    75°; Humberside, UK: 82°; Jersey, UK: 82°;London-Gatwick: 93° (tied June record); and, Vasteras, Sweden: 84°.

A sustained generally warmer than normal pattern is now in place. That pattern will likely persist through at least July and August, paving the way for a warmer than normal summer throughout the region. Initially, extreme heat is unlikely, but that could change in July, especially if the emerging drought continues to deepen. One or more heatwaves are likely in July across the region.

The CFSv2, which is now moving into its skillful range for its monthly forecasts, and the EPS weeklies favor a warmer than normal July across the region.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.4°C for the week centered around June 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.32°C and the ENSO Region 3.4 anomaly has averaged -0.43°C. Neutral-cool conditions will likely prevail through mid-summer. The probability of the development of a La Niña event during late summer or early autumn has increased in recent weeks.

The SOI was +4.92 today.

Today, the preliminary Arctic Oscillation (AO) figure was -0.151.

On June 23, the MJO was in Phase 1 at an amplitude of 1.818 (RMM). The June 22-adjusted amplitude was 1.814.

Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn.

This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Since 1981, there were four such cases that saw the MJO meet or exceed those thresholds during the June 1-10 period: 2002, 2006, 2007, and 2015. While the four cases were evenly split between cooler and warmer than normal during the second half of June, 3 of those 4 cases saw a warmer to much warmer than normal July. This could be an early indication that a summer that will start with near normal temperatures overall (June) could turn warmer than normal afterward.

Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. Taking into consideration the MJO, that transition could begin some time during the closing 10 days of June. Further, the cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City.

Just as had been the case last year, July and August could feature warm anomalies in the East. July-August 2019 saw 13 days on which the temperature reached or exceeded 90° in New York City.

Based on sensitivity analysis applied to the latest guidance, there is an implied 96% probability that New York City will have a warmer than normal June. June will likely finish with a mean temperature near 73.8°.

[SACRUS]

a

6/24

LGA: 89
EWR: 88
ACY: 88
JFK: 88
ISP: 88
NYC: 86
TEB: 86
BLM: 86
TTN: 85
PHL: 85
New Brnswck: 85

[Rtd208]

High for the day was 86 here.

[CIK62]

The last 6 days of June are averaging 78degs., or 3.5degs. AN.

Month to date is  +2.2[72.8].         June should end at  +2.4[73.8].

73* here at 6am, thin overcast, some blue.     75* by 9am.         77* by Noon.      79* by 3pm but it clouded up and cool breeze dropped it to 76* at 3:30pm.

GFS back to the usual antics: 14 90-Degree Days incoming and you can shoot your fireworks off in 100 degree heat, July 4th. itself.

[SACRUS]

Down to a comfortable 60/54 last night.  Upto 776 now as clouds cut NJ in half SW to NE. More warm and dry next day into the mid 80s, little if any showers or rain.  Warming tomorrow to the upper 80s  and by Saturday perhaps the hottest day of the season (so far) as 850 temps exceed 18c ahead of storms overnight.  Warmer / drier by Sunday pm and near 90.

ULL cutoff now coming in to view but these are hard to handle so a day or so timing may be needed as buffer.  6/30 - 7/30 ULL over the northeast E/ NE flow for a few days and perhasps clouds and storms one or two of those days.  Overall warm airmass  with ULL trapped in the weakness part 3.  Both GFS and ECM pushing ULL off shore by the fourth of July with a more N/NW flow to warm things back up later  that day and Sunday the heat is on.  Beyond there looks like sustained warmth with a flatter ridge keeping the flow hot.     

[alexj7]

Potential for severe storms on Saturday.

[bluewave]

We need some help from any convection on Saturday to make it out of the top 10 driest Junes.

 

Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Jun
Click column heading to sort ascending, click again to sort descending.

Rank	Year	Total Precipitation	Missing Count
1	1949	0.02	0
2	1999	0.59	0
3	2020	0.98	6
-	1894	0.98	0
4	1901	1.00	0
5	1880	1.14	0
6	1966	1.17	0
7	1898	1.25	0
8	1906	1.26	0
9	1965	1.27	0
-	1908	1.27	0
10	1873	1.28	0

 

Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Jun
Click column heading to sort ascending, click again to sort descending.

Rank	Year	Total Precipitation	Missing Count
1	1949	0.03	0
2	1999	0.50	0
3	2020	0.76	6
4	1988	0.94	0
5	1965	1.14	0
6	1978	1.30	0
7	1986	1.43	0
-	1963	1.43	0
8	1966	1.44	0
9	1954	1.48	0
10	1979	1.51	0

[Brian5671]

out of range NAM but shows a stripe of decent rains Sat Night/Sun

-

[Rtd208]

Current temp is 85 here.

[gravitylover]

2 hours ago, Brian5671 said:

out of range NAM but shows a stripe of decent rains Sat Night/Sun

-

Our luck it'll come hard and fast and just run off.

[LongBeachSurfFreak]

1 hour ago, gravitylover said:

Our luck it'll come hard and fast and just run off.

Exactly. What we need is an actual low to track slowly over us, with onshore flow and stratiform rains. A summer nor’easter type deal where it rains light to moderate for a couple days. When the ground gets super dry it hardens up and runs off very easily 

[TriPol]

1 minute ago, LongBeachSurfFreak said:

Exactly. What we need is an actual low to track slowly over us, with onshore flow and stratiform rains. A summer nor’easter type deal where it rains light to moderate for a couple days. When the ground gets super dry it hardens up and runs off very easily 

A tropical storm that stalls over Long Island would be ideal.

[Dan76]

20 minutes ago, LongBeachSurfFreak said:

Exactly. What we need is an actual low to track slowly over us, with onshore flow and stratiform rains. A summer nor’easter type deal where it rains light to moderate for a couple days. When the ground gets super dry it hardens up and runs off very easily 

When's the last time we had something like that? 1987?

[forkyfork]

i would rather get 60's and inches of rain with these cutoffs than dry and near normal

[Snowlover11]

we need rain badly, my car is suppose to be blue not green with massive amounts of bird turd!

[nycwinter]

19 minutes ago, forkyfork said:

i would rather get 60's and inches of rain with these cutoffs than dry and near normal

thank goodness ny reservoir levels are at 94% capacity.. with this prolonged dry weather pattern we would have water restrictions.

[Cfa]

Snuck in a 90 here, third one so far. Down to 79 now with cloud cover.

[doncat]

Rain 0.18" past 20 days...1.48" for month...3.25" since May 1st.

[SACRUS]

6/25

LGA: 89
EWR: 88
NYC: 87
ACY: 87
TEB: 86
ISP: 85
JFK: 85
PHL: 84
New Brnswck: 84
BLM: 84
TTN: 84

[Rtd208]

High for the day was 87 here. Plenty of mid-upper 80's temps w/occasional low 90's so far this summer. 

Current temp 76

[donsutherland1]

Tomorrow will be another similar day as today. Temperatures should again climb into the middle and perhaps even upper 80s.

A sustained generally warmer than normal pattern is now in place. That pattern will likely persist through at least July and August, paving the way for a warmer than normal summer throughout the region. Initially, extreme heat is unlikely, but that could change in July, especially if the emerging drought continues to deepen. One or more heatwaves are likely in July across the region.

The CFSv2, which is now moving into its skillful range for its monthly forecasts, and the EPS weeklies favor a warmer than normal July across the region.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.4°C for the week centered around June 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.32°C and the ENSO Region 3.4 anomaly has averaged -0.43°C. Neutral-cool conditions will likely prevail through mid-summer. The probability of the development of a La Niña event during late summer or early autumn has increased in recent weeks.

The SOI was -3.87 today.

Today, the preliminary Arctic Oscillation (AO) figure was -0.258.

On June 24, the MJO was in Phase 1 at an amplitude of 1.818 (RMM). The June 23-adjusted amplitude was 1.818.

Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn.

This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period. Since 1981, there were four such cases that saw the MJO meet or exceed those thresholds during the June 1-10 period: 2002, 2006, 2007, and 2015. While the four cases were evenly split between cooler and warmer than normal during the second half of June, 3 of those 4 cases saw a warmer to much warmer than normal July. This could be an early indication that a summer that will start with near normal temperatures overall (June) could turn warmer than normal afterward.

Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. Taking into consideration the MJO, that transition could begin some time during the closing 10 days of June. Further, the cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City.

Just as had been the case last year, July and August could feature warm anomalies in the East. July-August 2019 saw 13 days on which the temperature reached or exceeded 90° in New York City.

Based on sensitivity analysis applied to the latest guidance, there is an implied 98% probability that New York City will have a warmer than normal June. June will likely finish with a mean temperature near 73.8°.