snowman19 Posted January 19 Share Posted January 19 4 minutes ago, NittanyWx said: Our peak warm spells this winter have been in MJO 8 1, what does that tell you? Back in Jan/Feb of 1998, we spent the overwhelming amount of time in MJO phase 8 and we all know how well that went for us 1 Link to comment Share on other sites More sharing options...
the_other_guy Posted January 19 Share Posted January 19 11 minutes ago, NittanyWx said: Our peak warm spells this winter have been in MJO 8 1, what does that tell you? and they’ve been accompanied by a lot of posts asking why MJO doesn’t work anymore when predicting patterns. interesting take on this and I appreciate your post 5 Link to comment Share on other sites More sharing options...
the_other_guy Posted January 19 Share Posted January 19 2 hours ago, EastonSN+ said: I wonder when the last time DC had more snowfall than CPK? Was it really 09/10? yeah, but this is a shit winter for them too. You’re comparing two piles of shit and wondering who’s is bigger 09/10 was good for all. 1 Link to comment Share on other sites More sharing options...
Stormlover74 Posted January 19 Share Posted January 19 5 minutes ago, the_other_guy said: yeah, but this is a shit winter for them too. You’re comparing two piles of shit and wondering who’s is bigger 09/10 was good for all. They might be near their seasonal average to date after today Link to comment Share on other sites More sharing options...
the_other_guy Posted January 19 Share Posted January 19 2 minutes ago, Stormlover74 said: They might be near their seasonal average to date after today In a couple decades, this will be near your seasonal average too haha 1 Link to comment Share on other sites More sharing options...
SnowGoose69 Posted January 19 Share Posted January 19 3 minutes ago, Stormlover74 said: They might be near their seasonal average to date after today Yeah I believe 8-10 inches through this stage for them is close to that though for BWI its likely still below 2 Link to comment Share on other sites More sharing options...
NittanyWx Posted January 19 Share Posted January 19 12 minutes ago, SnowGoose69 said: Yeah I believe 8-10 inches through this stage for them is close to that though for BWI its likely still below I went back into my notes yesterday after you spoke about the lagged fast, slow response...i had a paper from Yadav on the subject: scholar.google.com/scholar_url?url=https://repository.library.noaa.gov/view/noaa/48317/noaa_48317_DS1.pdf&hl=en&sa=X&ei=nZKqZZTgGMrJy9YPkL-OiAY&scisig=AFWwaeYaGB4mXHwpJvzQ8GUFrEZc&oi=scholarr 2 Link to comment Share on other sites More sharing options...
NittanyWx Posted January 19 Share Posted January 19 For anyone interested, there's also this paper on the subject: Time-Lagged Response of the Antarctic and High-Latitude Atmosphere to Tropical MJO Convection in: Monthly Weather Review Volume 146 Issue 4 (2018) (ametsoc.org) With this wonderful caveat: 'However, the time lag between the MJO and the Antarctic atmosphere has been found to vary between less than 7 and greater than 20 days.' Go forecast that. Impact could be less than 7, could be greater than 20 days. But don't worry, we promise this is adding skill... 4 Link to comment Share on other sites More sharing options...
JustinRP37 Posted January 19 Share Posted January 19 51 minutes ago, NittanyWx said: Our peak warm spells this winter have been in MJO 8 1, what does that tell you? Thanks for all this. I was laughed at for suggesting we put way too much emphasis on the MJO when there are plenty of other factors to look into. The MJO plays a role, but like everything in environmental science and meteorology there are millions of things going on all at once so we can never pick just one variable and say this is the be all end all. Just like the people that say snowless warm winters help tick populations, we now know that is not true. 1 Link to comment Share on other sites More sharing options...
bluewave Posted January 19 Share Posted January 19 1 hour ago, NittanyWx said: Our peak warm spells this winter have been in MJO 8 1, what does that tell you? That isn’t the case. The MJO didn't go into 8 but weakened after the warm 4-7 phases. Then the convection fired in 2 which lead to the very strong trough out West with continuing warmth into mid-January. Another reason you are missing the understanding of a lagged response at times is the resulting Jet extensions which take time for the pattern to fully manifest. So it’s an unreasonable expectation for the MJO to always behave in an instantaneous manner. But there are times when the other factors align to give a more instantaneous response. 1 Link to comment Share on other sites More sharing options...
NittanyWx Posted January 19 Share Posted January 19 11 minutes ago, bluewave said: That isn’t the case. The MJO didn't go into 8 but weakened after the warm 4-7 phases. Then the convection fired in 2 which lead to the very strong trough out West with continuing warmth into mid-January. This is inaccurate. We had a >1 St Dev RMM phase 1 response for the majority of end December. By Zhou's definition for a coherent MJO signal, this is significant. I hate wheeler plots, but Zhou uses them for the MJO composites so it's worth remembering that. If you want to look at the VP space you had a coherent subsidence response in the maritime continent over peak warm pool areas in mid to late December: You can argue it was less amplified (true) but I don't view that as an incoherent progression in the VP space. Link to comment Share on other sites More sharing options...
bluewave Posted January 19 Share Posted January 19 21 minutes ago, NittanyWx said: This is inaccurate. We had a >1 St Dev RMM phase 1 response for the majority of end December. By Zhou's definition for a coherent MJO signal, this is significant. I hate wheeler plots, but Zhou uses them for the MJO composites so it's worth remembering that. If you want to look at the VP space you had a coherent subsidence response in the maritime continent over peak warm pool areas in mid to late December: You can argue it was less amplified (true) but I don't view that as an incoherent progression in the VP space. The VP anomaly charts are probably closer to the truth with the strongest convection in region 7 during December which was displaced further west than was typical for a canonical El Niño response. The actual convection was off the charts near Australia with all time record rainfall and dewpoints. The previous records were established during La Ninas. This is why the records were so noteworthy for a strong El Niño. But not surprising given the nearly warmest SSTs there on record for this time of year. So it’s also no surprise that the forcing was more prominent in those regions and weaker through some of the other MJO phases on the transit. This is why the RMM charts don’t always tell the whole story. But there are times that they do also. Even in the met community there have been papers written on the strengths and weaknesses of the various approaches at different times. The convection shifted over to phase 2 in early January creating the big pattern shift from strong ridge near the Upper Midwest in December to deep trough near the four corners states. Very predictable shifts given the change in the location of the primary convective forcing. Link to comment Share on other sites More sharing options...
NittanyWx Posted January 19 Share Posted January 19 22 minutes ago, bluewave said: The VP anomaly charts are probably closer to the truth with the strongest convection in region 7 during December which was displaced further west than was typical for a canonical El Niño response. The actual convection was off the charts near Australia with all time record rainfall and dewpoints. The previous records were established during La Ninas. This is why the records were so noteworthy for a strong El Niño. But not surprising given the nearly warmest SSTs there on record for this time of year. So it’s also no surprise that the forcing was more prominent in those regions and weaker through some of the other MJO phases on the transit. This is why the RMM charts don’t always tell the whole story. But there are times that they do also. Even in the met community there have been papers written on the strengths and weaknesses of the various approaches at different times. The convection shifted over to phase 2 in early January creating the big pattern shift from strong ridge near the Upper Midwest in December to deep trough near the four corners states. Very predictable shifts given the change in the location of the primary convective forcing. So you're arguing a lagtime of two weeks effectively. Peak convection in this area is Jan 1-5. We got cold here Jan 14-20 and lingering into the 21st. Why was the lagtime two weeks and not one week? Most of the MJO lagtime papers argue one week. I've been on the receiving end of a lot of forecasts that purported to use the MJO for last week and extending into this one, and I can tell you that very few of them got the timing of this right, particularly when it came to the west and Canada. I can tell you why I made my forecast cold MLK week...it was because I saw an increased blocking signature developing first week of Jan, particularly Atlantic side and a potential for a displaced lobe of the TPV being cut off and pinched into western Canada and eventually that moving eastward. I saw the signal for this in late December, used it accordingly. The impetus for my view was blocking, which the MJO lagged signature incorrectly is predicting would linger into next week in the AK/EPO regions..it isn't. So if your two week (to be clear, this is the argument) lagtime is supposed to continue here, I'd be expecting an MJO P3 response next week, and I'd be expecting blocking to continue across the upper latitudes. Neither of those things are happening. What's the lag time now? 2 Link to comment Share on other sites More sharing options...
bluewave Posted January 19 Share Posted January 19 53 minutes ago, NittanyWx said: So you're arguing a lagtime of two weeks effectively. Peak convection in this area is Jan 1-5. We got cold here Jan 14-20 and lingering into the 21st. Why was the lagtime two weeks and not one week? Most of the MJO lagtime papers argue one week. I've been on the receiving end of a lot of forecasts that purported to use the MJO for last week and extending into this one, and I can tell you that very few of them got the timing of this right, particularly when it came to the west and Canada. I can tell you why I made my forecast cold MLK week...it was because I saw an increased blocking signature developing first week of Jan, particularly Atlantic side and a potential for a displaced lobe of the TPV being cut off and pinched into western Canada and eventually that moving eastward. I saw the signal for this in late December, used it accordingly. The impetus for my view was blocking, which the MJO lagged signature incorrectly is predicting would linger into next week in the AK/EPO regions..it isn't. So if your two week (to be clear, this is the argument) lagtime is supposed to continue here, I'd be expecting an MJO P3 response next week, and I'd be expecting blocking to continue across the upper latitudes. Neither of those things are happening. What's the lag time now? Phase 2 is a very warm phase for us during an El Niño and the convection was focused there for much of early January so not much in the way of a lag there. But the lag this month was with the cold this week was through 3 enhanced by the multiple wave breaks but only lagged by about 3-7 days. The moderation coming up after the weekend has elements of 4 and beyond. Plus we have the interaction with what has happened with the dramatic reversal closer to the Arctic. Link to comment Share on other sites More sharing options...
Heisy Posted January 19 Share Posted January 19 Patience required…. Check back in after 2 weeks imo. This event today made me even hungrier for the big dog. One day…. 1 1 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 1 minute ago, Heisy said: Patience required…. Check back in after 2 weeks imo. This event today made me even hungrier for the big dog. One day… . Ugly. I don’t know if we recover from such a horrible look. It took weeks to get one cold week from that same H5 in December. 2 1 Link to comment Share on other sites More sharing options...
NittanyWx Posted January 19 Share Posted January 19 58 minutes ago, bluewave said: Phase 2 is a very warm phase for us during an El Niño and the convection was focused there for much of early January so not much in the way of a lag there. But the lag this month was with the cold this week was through 3 enhanced by the multiple wave breaks but only lagged by about 3-7 days. The moderation coming up after the weekend has elements of 4 and beyond. Plus we have the interaction with what has happened with the dramatic reversal closer to the Arctic. My personal view is that if your lag time changes from next to nothing to 7 days and you don't have a predictive way to determine how long the lag actually is in a given moment, it is almost a hindrance to getting the forecast right in the timeframe you need it to be right. The models are also assimilating this data too, so I'm not really sure where the skill score improvement is coming from. I think the strato coupling had merit and I used it for this period. 1 Link to comment Share on other sites More sharing options...
snowman19 Posted January 19 Share Posted January 19 8 minutes ago, Allsnow said: Ugly. I don’t know if we recover from such a horrible look. It took weeks to get one cold week from that same H5 in December. Lol at his post. We aren’t just magically turning arctic cold again like flipping a light switch after that huge AK vortex and PAC jet extension floods all of Canada and the CONUS with Pacific maritime air. In 2 weeks we are already into February 2 3 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 3 minutes ago, snowman19 said: Lol at his post. We aren’t just magically turning arctic cold again like flipping a light switch after that huge AK vortex and PAC jet extension floods all of Canada and the CONUS with Pacific maritime air. In 2 weeks we are already into February Yeah, we saw how long it took just to get cold enough to snow. I will say NYC had some very bad luck in not getting more then 1.8 the last two weeks 2 Link to comment Share on other sites More sharing options...
bluewave Posted January 19 Share Posted January 19 22 minutes ago, NittanyWx said: My personal view is that if your lag time changes from next to nothing to 7 days and you don't have a predictive way to determine how long the lag actually is in a given moment, it is almost a hindrance to getting the forecast right in the timeframe you need it to be right. The models are also assimilating this data too, so I'm not really sure where the skill score improvement is coming from. I think the strato coupling had merit and I used it for this period. I wasn’t primarily using it to make the forecast for this cold period. The models actually did a decent job. But someone asked about the pattern and how lags worked out. So it was to explain what input it had to the overall pattern. The edge for MJO forecasting usually further out in time say 10-15 days to a month and beyond. The models generally handle short term transitions day 1-5 and 6-10 pretty well . But there are systemic biases at play longer range that once corrected lead to better long range forecast outcomes. Link to comment Share on other sites More sharing options...
MJO812 Posted January 19 Share Posted January 19 Huge PNA ridge out west on the euro at 240. That's our next threat. 2 2 Link to comment Share on other sites More sharing options...
Brian5671 Posted January 19 Share Posted January 19 8 minutes ago, MJO812 said: Huge PNA ridge out west on the euro at 240. That's our next threat. Ensembles....day 10 on OP is fantasy 2 Link to comment Share on other sites More sharing options...
bluewave Posted January 19 Share Posted January 19 1 hour ago, Allsnow said: Yeah, we saw how long it took just to get cold enough to snow. I will say NYC had some very bad luck in not getting more then 1.8 the last two weeks That’s what I was commenting on a few weeks back. We were discussing the window, but I was concerned it would be too short to put together more than a 1-3 or 2-4 type event. 16-17 was a really unique winter which was very warm and we seemed to get short term pattern changes which produced blizzards. But ever since 18-19, we needed more time to put together bigger events. Like we saw in December 2020 with the decent pattern becoming established early on leading to the great event around the 17th. 2 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 15 minutes ago, MJO812 said: Huge PNA ridge out west on the euro at 240. That's our next threat. Cutoff season Link to comment Share on other sites More sharing options...
SBUWX23 Posted January 19 Share Posted January 19 17 minutes ago, MJO812 said: Huge PNA ridge out west on the euro at 240. That's our next threat. Trough axis is again to far west. 1 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 53 minutes ago, bluewave said: I wasn’t primarily using it to make the forecast for this cold period. The models actually did a decent job. But someone asked about the pattern and how lags worked out. So it was to explain what input it had to the overall pattern. The edge for MJO forecasting usually further out in time say 10-15 days to a month and beyond. The models generally handle short term transitions day 1-5 and 6-10 pretty well . But there are systemic biases at play longer range that once corrected lead to better long range forecast outcomes. I just don’t think we will get long favorable windows in a strong Nino imo. NYC missed the first event to the north(white rain to start), under 2 in the second event with higher totals all around and a miss south with the 3rd event that dropped 4-8 in DCA. I just think the city locally was just unlucky not to get more 3 Link to comment Share on other sites More sharing options...
MJO812 Posted January 19 Share Posted January 19 Just now, SBUWX23 said: Trough axis is again to far west. Yep We can work that out 1 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 Just now, MJO812 said: Yep We can work that out No cold 1 Link to comment Share on other sites More sharing options...
MJO812 Posted January 19 Share Posted January 19 2 minutes ago, Allsnow said: No cold That's a problem . Maybe a good timed low. CooL is haf enthused 1 Link to comment Share on other sites More sharing options...
Allsnow Posted January 19 Share Posted January 19 Just now, MJO812 said: That's a problem . Maybe a good timed low. CooL is haf enthused Love Cool but I’m not as enthused. I hope he is correct 1 Link to comment Share on other sites More sharing options...
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