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Pattern Freezing Ferocious February

Clayton said:
You may be right, but it's almost worthless if you don't get it to freeze over because without a freeze over you'll still have to go to school, work, etc. Then it's almost like the storm was for nothing because staying home without the stress of work or school is the second best part of the storm. Do that's why I'm always kinda iffy about marginal events even if they are big. For example, even with all the snow in the early December storm, many people still had to go to work, etc the next day so it was almost as if the storm was for nothing. Get what I mean?
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I bet you’re the type of person who gets mad when the forecast was calling for 6 inches of snow but you only got 5.
 
olhausen said:
I bet you’re the type of person who gets mad when the forecast was calling for 6 inches of snow but you only got 5.
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At least in my case he's only correct when it's a little wet snow. I've seen plenty a time where a nice wet snow, 2"+, has had everything close down the day after. Yes, it's business as usual quicker but still.

Shoot my college closed for snow and I never accumulated. It's the south people freak out.
 
Storm5 said:
Now we have all globals with a big shot and an active storm track next week

Does that mean we see something ??? No it does not . But as Eric , jon and others have pointed out the models are slowly correcting to a colder stormier pattern
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Yes, that is exactly right. The GFS continues to improve. The Euro continues to improve. The CMC is showing hints of wintry weather. The CFS continues to look better as we close out the month. I don't know why there's despair and dismay that the PV isn't moving over South Carolina in 3 days. The general evolution to a colder, potentially stormier pattern is on track, and even possibly ahead of schedule. Cold is nearby. Apparently, now it's beginning to look like precipitation will be nearby as well. And, all of this is happening (or appears to be happening) during a favorable climo time. There is not one legitimate reason to be discouraged at this time, unless your only threshold for satisfaction is snow or ice falling immediately.
 
The Euro continues to amplify the MJO in the Western Pacific and Western Hemisphere, and is looking more like the GFS every day. Now brings the MJO to nearly 3.5 sigma and even that may not be strong enough.
output_t9VmAH.gif

A few important take aways worth bringing up here that I gleaned from reading several pieces of scientific literature last night regarding the ECMWF's handling of MJO events in the Maritime Continent
  • The MJO predictability across the Maritime Continent appears to be dependent on the amount of convection and boundary layer warmth in the Western Pacific. Warmer initial SSTs and less convection preceding MJO events that propagate across the Maritime Continent are generally more predictable than those w/ a singular, monopole of deep convection.
  • Drier western Pacific helps generate a rossby wave like response that increases meridional flux of moisture which allows the MJO to propagate more easily across the Maritime Continent
  • The fractional contribution of surface winds is larger than convection (OLR) in RMM which is a profound weakness in the index
  • The European actually has a wet bias over the Maritime Continent due to its poor representation of important topographic features which interfere w/ low-level latent heat fluxes and surface wind exchanges. This wet bias here strengthens the Walker Circulation and creates a corresponding cool bias in the east-central Pacific equatorial cold tongue.
  • The stronger diurnal cycle during the northern hemisphere summer and El Nino increases the frequency of MJO blocking by the Maritime Continent because the incident solar radiation is stronger which hastens the diurnal cycle of convection over the archipelago that destructively interferes w/ the MJO
  • The diurnal cycle in convection over the Maritime Continent interferes with the MJO by competing for moisture, and impacts to the large-scale circulation through generation of sea breeze circulations, etc.

The following diagram shows RMM MJO bias vectors for the ECMWF, JMA, and NCEP GFS models from Ichikawa and Inatsu (2017) according to each MJO phase. Note here that the Euro and JMA are on average too slow w/ the MJO in general (for example during a Maritime Continent MJO forecast reality may be closer to phase 5 while a Euro/JMA forecast depicts the MJO closer to phase 4, etc.). Also, while the NCEP GFS tends to have an overall oversimplification bias for MJO events as Larry has discussed the past few days, this bias only really occurs in phases 6,7,8, & 1 (western Pacific & Western Hemisphere), while the biases in the Maritime Continent are actually smaller than either the JMA or ECMWF models. This suggests that the GFS is in fact better at forecasting MJO events in the Maritime Continent (phase 4-5) than any other global model, which is where the MJO has been the past week and change.
ECMWF, JMA, & NCEP MJO Bias vectors Ichikawa and Inatsu (2017).png
 
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Rain Cold said:
Yes, that is exactly right. The GFS continues to improve. The Euro continues to improve. The CMC is showing hints of wintry weather. The CFS continues to look better as we close out the month. I don't know why there's despair and dismay that the PV isn't moving over South Carolina in 3 days. The general evolution to a colder, potentially stormier pattern is on track, and even possibly ahead of schedule. Cold is nearby. Apparently, now it's beginning to look like precipitation will be nearby as well. And, all of this is happening (or appears to be happening) during a favorable climo time. There is not one legitimate reason to be discouraged at this time, unless your only threshold for satisfaction is snow or ice falling immediately.
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Great post! I think the discouragement is when those who didn't get much snow this winter take the long range as gospel and don't want to wait for changes. No matter how many posts are made proving things are getting better their view doesn't change. Patience is always key for us anyway when tracking winter weather.
 
Webberweather53 said:
The Euro continues to amplify the MJO in the Western Pacific and Western Hemisphere, and is looking more like the GFS every day. Now brings the MJO to nearly 3.5 sigma and even that may not be strong enough.
View attachment 3568

A few important take aways worth bringing up here that I gleaned from reading several pieces of scientific literature last night regarding the ECMWF's handling of MJO events in the Maritime Continent
  • The MJO predictability across the Maritime Continent appears to be dependent on the amount of convection and boundary layer warmth in the Western Pacific. Warmer initial SSTs and less convection preceding MJO events that propagate across the Maritime Continent are generally more predictable than those w/ a singular, monopole of deep convection.
  • Drier western Pacific helps generate a rossby wave like response that increases meridional flux of moisture which allows the MJO to propagate more easily across the Maritime Continent
  • The fractional contribution of surface winds is larger than convection (OLR) in RMM which is a profound weakness in the index
  • The European actually has a wet bias over the Maritime Continent due to its poor representation of important topographic features which interfere w/ low-level latent heat fluxes and surface wind exchanges. This wet bias here strengthens the Walker Circulation and creates a corresponding cool bias in the east-central Pacific equatorial cold tongue.
  • The stronger diurnal cycle during the northern hemisphere summer and El Nino increases the frequency of MJO blocking by the Maritime Continent because the incident solar radiation is stronger which hastens the diurnal cycle of convection over the archipelago that destructively interferes w/ the MJO
  • The diurnal cycle in convection over the Maritime Continent interferes with the MJO by competing for moisture, and impacts to the large-scale circulation through generation of sea breeze circulations, etc.

The following diagram shows RMM MJO bias vectors for the ECMWF, JMA, and NCEP GFS models from Ichikawa and Inatsu (2017) according to each MJO phase. Note here that the Euro and JMA are on average too slow w/ the MJO in general (for example during a Maritime Continent MJO forecast reality may be closer to phase 5 while a Euro/JMA forecast depicts the MJO closer to phase 4, etc.). Also, while the NCEP GFS tends to have an overall oversimplification bias for MJO events, this bias only really occurs in phases 6,7,8, & 1 (western Pacific & Western Hemisphere), while the biases in the Maritime Continent are actually smaller than either the JMA or ECMWF models. This suggests that the GFS is in fact better at forecasting MJO events in the Maritime Continent (phase 4-5) than any other global model, which is where the MJO has been the past week and change.
View attachment 3570
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Awesome stuff. Thanks for the detailed posts . I've learned more about the MJO this winter vs previous years combined .

Sent from my SM-J320VPP using Tapatalk
 
Rain Cold said:
Yes, that is exactly right. The GFS continues to improve. The Euro continues to improve. The CMC is showing hints of wintry weather. The CFS continues to look better as we close out the month. I don't know why there's despair and dismay that the PV isn't moving over South Carolina in 3 days. The general evolution to a colder, potentially stormier pattern is on track, and even possibly ahead of schedule. Cold is nearby. Apparently, now it's beginning to look like precipitation will be nearby as well. And, all of this is happening (or appears to be happening) during a favorable climo time. There is not one legitimate reason to be discouraged at this time, unless your only threshold for satisfaction is snow or ice falling immediately.
Click to expand...

One million likes! Some people have very short memories and are never content. One year ago. KATL had these highs 2/1-15:
71, 71, 57, 50, 52, 71, 67, 67, 64, 64, 69, 72, 67, 72, 62. There were only two barely colder than normal days and 9 much warmer than normal days. Their average was near the normal for Brunswick, GA! Contrast to how it looks now with KATL looking to have a first half of Feb likely no warmer than the normal for Huntsville and quite possibly more like the normal for Nashville.
 
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Storm5 said:
Awesome stuff. Thanks for the detailed posts . I've learned more about the MJO this winter vs previous years combined .

Sent from my SM-J320VPP using Tapatalk
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Thanks! Feel free to ask any other questions regarding the MJO haha it's one of the few phenomena I have an extremely robust background in, even more so than just about everything else in atmospheric science lol.
 
JMA, EPS and GEFS some agreement on low off the coast with a banana high.

ecmwf-ens_mslpa_us_8.png


jma_mslpaNorm_us_8.png
 
Kylo said:
JMA, EPS and GEFS some agreement on low off the coast with a banana high.

ecmwf-ens_mslpa_us_8.png


jma_mslpaNorm_us_8.png
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If we could shift that entire field 150ish miles SE on the JMA, we'd be in business!
 
Someone else can give more details but the 12z EPS still has that dumb long range subtropical ridge over the whole US that isn't likely to actually happen.
 
JMA has a Miller A in the period I'm kind of keeping tabs on (after the possible mid south storm). Climo wise it's likely better for North GA and Upstate SC though.
 
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