February 2020 General Discussions & Observations Thread

[wdrag]

Good Saturday morning, Feb 8.

Minor events next 48hrs nw NJ... produce a little snow, especially high terrain Sussex County NJ.  Starts maybe late this afternoon with FGEN, or else a period late tonight with the trailing short wave pout of the OH Valley, then a wet snowfall possible Sunday night turning to rain Monday morning. Should see an inch or two total for Sussex County NJ high terrain by Monday morning. I've added the HRRRX from 06z/8. Seems a little gong ho in nw NJ but if occurs, also allows NYC to see some sort of very light snowfall tonight. Operational HRRR is trying to show something similar but just w of NYC.

I am not liking the pattern but noticed CPC is running a little cooler these next several weeks with an active pattern. Here is their outlook issued yesterday for weeks 3-4.  We might yet expand the snowfall sample size (sometime in the next 4 weeks). I know unlikely, but stats are comprised of outliers as well. Thats all I can root for. 719A/8

 

[bluewave]

15 hours ago, Allsnow said:

I’m not sure about the Ao. The Pv being so strong I don’t think has a effect on it. (I could be wrong) We really needed strat hits with such a strong PV and never got them. The Ao is so positive because of strong storm by the pole I believe..... @bluewave might know more 
 

I know we had some higher hgts in Greenland to start December. It obviously wasn’t a true -nao but helped sne score a good storm. Since then, yes it’s been MIA. The vortex near Greenland certainly doesn’t help. 

There has been some research that the IOD could possibly impact the NAO and AO. Maybe the record +IOD from November into December was in some way responsible. Some of our other extremely +AO +NAO events were preceded by strong MJO 2-3 forcing. It could be that the IO standing wave from November into mid-December played a role. But we’ll  probably need a a study to confirm.

https://journals.ametsoc.org/doi/10.1175/JCLI3577.1?mobileUi=0&

The dominant pattern of atmospheric variability in the North Atlantic sector is the North Atlantic Oscillation (NAO). Since the 1970s the NAO has been well characterized by a trend toward its positive phase. Recent atmospheric general circulation model studies have linked this trend to a progressive warming of the Indian Ocean. Unfortunately, a clear mechanism responsible for the change of the NAO could not be given. This study provides further details of the NAO response to Indian Ocean sea surface temperature (SST) anomalies. This is done by conducting experiments with a coupled ocean–atmosphere general circulation model (OAGCM). The authors develop a hypothesis of how the Indian Ocean impacts the NAO.

 

By analyzing model simulations we found that the South Asian jet can act as a waveguide with circumglobal teleconnection in the Northern Hemisphere. The meridional wind pattern, associated with this circumglobal teleconnection, is connected with the North Atlantic Oscillation. A warming/cooling in the Indian Ocean, especially in the western Indian Ocean, produces anomalies in the South Asian jet. The waveguiding effect of the South Asian jet carries the perturbation into the North Atlantic sector and leads to a NAO-like response.

The observed recent positive trend in the NAO has likely contributions from the observed warming in the Indian Ocean. Our analysis—confirmed by the observed trend in the western South Asian jet and the anomaly pattern of the 300-hPa winter meridional wind—indicates that the change of the NAO may be via the circumglobal pattern.

https://journals.ametsoc.org/doi/full/10.1175/JCLI-D-15-0502.1?mobileUi=0

The teleconnection patterns associated with phases 3 and 7 are also important for Atlantic blocking. In agreement with Lin et al. (2009) and Cassou (2008), 10–15 days after MJO phase 3 a positive NAO pattern develops over the Atlantic. We find that Atlantic blocking frequency is more than halved in association with the positive NAO pattern. In contrast, MJO phase 7 is followed by a negative NAO pattern, which coincides with a high-amplitude wavelike flow and an increase in blocking frequency. Atlantic blocking frequency is almost doubled following phase 7, reaching +16.5% relative to climatology. Approximately 14%–15% of all DJF Atlantic blocked days follow phase 7.

 

[NEG NAO]

2 hours ago, MJO812 said:

6z gfs looks nice 

GEFS says NO

[NEG NAO]

1 hour ago, CIK62 said:

The next 8 days are averaging 38.5degs., or 4degs. AN.

31* here at 6am.     31* at 7am.

Already the rest of February needs to be -3.3 just to get to Normal.     Looks like we will be +5.8 by the 25th.

WINTER Update:

Starting Dec. 01  +4.3.     Starting Dec. 22   +7.4.

The next 17 days are averaging 39degs., or 4degs. AN.(06Z, GFS)      3" of Snow on the 13th.      The EURO is in the 60's at this same time, but has snow on the 17th.    Who/What is responsible for this continuous stream of hash and trash?

3" snow on the 13th ????

here is euro for the 17th -will It be there at 12Z today ?

[bluewave]

12 hours ago, Brasiluvsnow said:

Thanks a lot BW appreciate it

No problem. The GEFS continues to correct warmer. Its cold bias has been a big factor this winter.
 

 

[Brian5671]

7 minutes ago, bluewave said:

No problem. The GEFS continues to correct warmer. Its cold bias has been a big factor this winter.
 

 

same ol pattern-any cold shot either doesn't happen or moderates as it gets closer in time.  GFS/GEFS terrible with the LR cold bias.  Best to stick with Euro/EPS

[NEG NAO]

 

[doncat]

Even with a strong nw  wind behind a departing record low pressure Feb storm, could only manage 29° for low.

[Allsnow]

GEFS at 12z with a cave towards the eps after next weekend. Lower hgts in ak with a zonal flow.

[Allsnow]

@NEG NAO can you use the proper thread for medium range threats. 

[snowman19]

20 minutes ago, Allsnow said:

GEFS at 12z with a cave towards the eps after next weekend. Lower hgts in ak with a zonal flow.

Shocking, troughing back into AK after 2/16 and the EPO floodgates open up. Say goodbye to any cold that was left in Canada. Looks like the models are also strengthening the SPV again. This may be all she wrote for winter coming up....

[MJO812]

5 minutes ago, snowman19 said:

Shocking, troughing back into AK after 2/16 and the EPO floodgates open up. Say goodbye to any cold that was left in Canada. Looks like the models are also strengthening the SPV again. This may be all she wrote for winter coming up....

My end date is mid April.

[bluewave]

4 hours ago, Brian5671 said:

same ol pattern-any cold shot either doesn't happen or moderates as it gets closer in time.  GFS/GEFS terrible with the LR cold bias.  Best to stick with Euro/EPS

We knew this last winter while the FV3 was the parallel before it became operational. 

https://www.wired.com/story/the-governments-new-weather-model-faces-a-storm-of-protest/

The government’s new weather forecast model has a slight problem: It predicts that outside temperatures will be a few degrees colder than what nature delivers. This “cold bias” means that local meteorologists are abandoning the National Weather Service in favor of forecasts produced by British and European weather agencies.

For the past few weeks, the National Weather Service has been forecasting snowfall that ends up disappearing, according to Doug Kammerer, chief meteorologist at WRC-TV in Washington, DC. “It’s just not performing well,” Kammerer says. “It has continued to show us getting big-time snowstorms in this area, where the European model will not show it.”

 

[Allsnow]

The eps basically ends February with the vortex back in Ak and southeast ridge. That’s probably a pretty mild look for us.

[tek1972]

Not to be negative but I think the winter is spent. Sure it can snow in March of course but I think it’s just one of those winters. 
 
 

Snow in March is great. It doesn't last lol

Sent from my SM-N975U using Tapatalk

[Stormlover74]

This will be a shock to the system 

.FRIDAY...Mostly sunny. Cooler with highs in the lower 30s. 

.FRIDAY NIGHT...Partly cloudy. Cooler with lows 10 to 15. Wind chill values as low as zero. 

.SATURDAY...Mostly sunny. Cold with highs in the upper 20s. Wind chill values as low as zero in the morning. 

[psv88]

15 minutes ago, Stormlover74 said:

This will be a shock to the system 

.FRIDAY...Mostly sunny. Cooler with highs in the lower 30s. 

.FRIDAY NIGHT...Partly cloudy. Cooler with lows 10 to 15. Wind chill values as low as zero. 

.SATURDAY...Mostly sunny. Cold with highs in the upper 20s. Wind chill values as low as zero in the morning. 

Good. Gotta keep the bugs at bay

[Stormlover74]

1 minute ago, psv88 said:

Good. Gotta keep the bugs at bay

If it verifies it will be our first <20 since 12/21

[donsutherland1]

2 hours ago, bluewave said:

We knew this last winter while the FV3 was the parallel before it became operational. 

https://www.wired.com/story/the-governments-new-weather-model-faces-a-storm-of-protest/

The government’s new weather forecast model has a slight problem: It predicts that outside temperatures will be a few degrees colder than what nature delivers. This “cold bias” means that local meteorologists are abandoning the National Weather Service in favor of forecasts produced by British and European weather agencies.

For the past few weeks, the National Weather Service has been forecasting snowfall that ends up disappearing, according to Doug Kammerer, chief meteorologist at WRC-TV in Washington, DC. “It’s just not performing well,” Kammerer says. “It has continued to show us getting big-time snowstorms in this area, where the European model will not show it.”

 

IMO, FV3 should not have been operationalized until the known biases that led to the initial delayed implementation were proved to have been fixed. The decision to rush its implementation was not good. If anything, the continuing issues raise questions about the FV3 core itself, namely whether it actually is better than what it replaced.

[Brian5671]

1 hour ago, Stormlover74 said:

This will be a shock to the system 

.FRIDAY...Mostly sunny. Cooler with highs in the lower 30s. 

.FRIDAY NIGHT...Partly cloudy. Cooler with lows 10 to 15. Wind chill values as low as zero. 

.SATURDAY...Mostly sunny. Cold with highs in the upper 20s. Wind chill values as low as zero in the morning. 

if the seasonal trend is any indicator-those projected temps will warm as we get closer

[Stormlover74]

Just now, Brian5671 said:

if the seasonal trend is any indicator-those projected temps will warm as we get closer

Probably.  No way ewr gets down near 10

[bluewave]

28 minutes ago, Stormlover74 said:

Probably.  No way ewr gets down near 10

Maybe NYC can drop below 20 for the first time since December. EPS has a quick Arctic high near 1040 MB. The northerly flow from Upstate NY doesn’t cross the warmer open Great Lakes. In any event, we quickly warm up a few days later.

 

[Animal]

9 hours ago, wdrag said:

Good Saturday morning, Feb 8.

Minor events next 48hrs nw NJ... produce a little snow, especially high terrain Sussex County NJ.  Starts maybe late this afternoon with FGEN, or else a period late tonight with the trailing short wave pout of the OH Valley, then a wet snowfall possible Sunday night turning to rain Monday morning. Should see an inch or two total for Sussex County NJ high terrain by Monday morning. I've added the HRRRX from 06z/8. Seems a little gong ho in nw NJ but if occurs, also allows NYC to see some sort of very light snowfall tonight. Operational HRRR is trying to show something similar but just w of NYC.

I am not liking the pattern but noticed CPC is running a little cooler these next several weeks with an active pattern. Here is their outlook issued yesterday for weeks 3-4.  We might yet expand the snowfall sample size (sometime in the next 4 weeks). I know unlikely, but stats are comprised of outliers as well. Thats all I can root for. 719A/8

 

Walt... nice call. Hopefully it occurs.

mt holly issued an alert for snow tomorrow night higher terrain 

[bluewave]

This was the 2nd warmest 1st week of February in Newark at +11.4.

Time Series Summary for NEWARK LIBERTY INTL AP, NJ
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Feb 1 to Feb 7	Missing Count
1	1991-02-07	45.2	0
2	2020-02-07	44.0	0
3	2006-02-07	43.4	0
4	2008-02-07	43.2	0
5	2012-02-07	42.0	0
6	2016-02-07	41.9	0
7	1973-02-07	40.6	0
8	1999-02-07	40.3	0
-	1990-02-07	40.3	0
9	1952-02-07	40.1	0
10	1997-02-07	39.4	0

[donsutherland1]

Following yesterday’s deep storm, a colder air mass moved into the region. Nevertheless, the high temperature reached 41° in New York City and the daily mean temperature was still 2° above normal.

Five photos from the New York Botanical Garden where the first crocus buds have broken forth. Whether they represent an accurate long-range forecast for the coming spring remains to be seen.

[Isotherm]

One tangential benefit of the semi-persistent +NAM/AO mode this winter is the amelioration of ice growth across the Arctic spatial domain. The current Arctic sea ice extent is the "best" it has been since 2010; still far below the multi-decadal mean, but ahead of all of the past 10 years.

 

 

 

Not far from the 2000-2010 average, either:

 

[MJO812]

14 minutes ago, Isotherm said:

One tangential benefit of the semi-persistent +NAM/AO mode this winter is the amelioration of ice growth across the Arctic spatial domain. The current Arctic sea ice extent is the "best" it has been since 2010; still far below the multi-decadal mean, but ahead of all of the past 10 years.

 

 

 

Not far from the 2000-2010 average, either:

 

What does this mean for our area ?

[donsutherland1]

February 2020 had a mean temperature of 44.1° during the first week in February, the 3rd warmest figure on record. 2020 was the 11th year since regular record keeping began in 1869 during which the first week of February had a mean temperature of 40° or above in New York City. All prior 10 cases saw a warmer than normal February. The mean monthly temperature was 38.2°. Eight of those cases occurred during 1990 or later.

Milder weather will begin to return to the region tomorrow. However, a short-lived push of cold air could occur during the second half of the coming week.

Consistent with the pattern and supported by most of the guidance, no significant snowfalls (6" or more) are likely in the major Middle Atlantic Cities through at least the first two weeks of February. There is a greater but still fairly low probability for Boston to see such a snowstorm.

The ENSO Region 1+2 anomaly was +0.2°C and the Region 3.4 anomaly was +0.8°C for the week centered around January 29. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.07°C and the ENSO Region 3.4 anomaly has averaged +0.52°C. The remainder of winter 2019-2020 will likely feature neutral-warm to weak El Niño conditions.

The SOI was +3.89 today.

Today, the preliminary Arctic Oscillation (AO) figure was +3.173.

During the second week of February, the AO could generally be at or above +2.000 following a peak of +4.000 or above. At the same time, the NAO will likely be positive and the PNA will likely be negative. Since 1950, there have been no 4" or greater snowstorms during February with such teleconnections in Philadelphia or New York City. Boston saw four, with the biggest being 10.2" on February 24-25, 1990. The biggest snowfalls in Philadelphia and New York City were 2.3" and 2.0" respectively.

Near or just after mid-month, the guidance brings the MJO into Phase 6. There remains some uncertainty concerning its amplitude and duration in Phase 6. Its amplitude and the state of the teleconnections will determine the overall pattern during the start of the second half of February.

During the February 10-29 period, when the MJO is in Phase 6 at low amplitude, the state of the PNA has the largest impact on temperatures in the Middle Atlantic region. For example, in New York City, the mean temperature for PNA+ cases during the 1981-2019 period was 34.1°. For PNA- cases, it was 41.7°. In contrast, when the MJO has an amplitude of 1.000 or above, the state of the AO is more important. During such cases, the mean temperature for AO+ cases was 40.9° while the mean temperature for AO- cases was 35.5°. The mean temperature for the entire February 10-29, 1981-2019 period was 36.5°.

At present, it is likely that the February 15-21 period will be warmer than normal as a whole with only transient cold shots.

No significant stratospheric warming is likely through February 15, but the upper stratosphere could warm toward mid-February. Wave 2 activity will remain relatively suppressed. Overall, most of the stratosphere is forecast to remain cold on the EPS through the second week of February.

On February 7, the MJO was in Phase 4 at an amplitude of 1.589 (RMM). The February 6-adjusted amplitude was 1.291.

Finally, a trace of snow was recorded in Atlanta following last year's first winter on record where not even a trace of snow was recorded there.

[psv88]

27 minutes ago, MJO812 said:

What does this mean for our area ?

Nothing

[Isotherm]

49 minutes ago, MJO812 said:

What does this mean for our area ?

 

Any short term effect would be negligible; however, if the trend continues, it would permit a greater reservoir of colder air to the north. That said, a conducive pattern is still required to deliver the air. Note, this is merely an early observation as the trend could also reverse. But greater arctic sea ice in the long term would be salutary in terms of global temperature leveling.