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Pattern Jammin' January

Rain Cold said:
I agree, but we really need to be smarter than this. Maybe smarter isn't the right term. But maybe we need to learn that there's a difference between something that is fun to look at and something that is realistic. The two are usually not the same in the weather world.
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Completely agree..... maybe I should've said those who look at it and take it for gospel that it will snow in their backyard are being set up for disappointment. Fact is when the ens are continuously showing a good snow mean, even if it's one or two members skewing it, it's a good sign just how close we are to something producing. The pattern is such that a small (relatively speaking) difference here or there with a ridge or trough placement or some other feature, as you mentioned above, could have huge implications for sensible weather. Pattern changes always bring chaos which generally is not met with patience Lol
 
mrdaddyman said:
This is what I have never completely understood about ensembles. How can you load different initial conditions into an ensemble model as initial atmospheric conditions, weather observations, measurements, etc. are already measured and defined at a current point in time? It's like taking a snapshot of the current weather conditions, varying or changing them to something different, and then loading them into the ensemble. If the ensembles start out with initial conditions that are varied or possibly incorrect, how the ensembles can be expected to create an accurate forecast further out in time. Are these variations that are loaded into the ensemble being done under the assumption that the current weather conditions may not have been accurately measured or sampled and therefore may actually be incorrect to begin with?
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It's essentially scenario forecasting. It's kind of like if you're planning to take your family to the beach this weekend for a nice holiday of fun in the sand. Your initial conditions are that the car works, your boss gives you the weekend off, the forecast is warm and sunny, and you are feeling good.

If you're like Billy Bob, you don't give it a second thought. But if you're like Geoffrey Von Enrich, III, you think it through. What will my weekend look like if my boss makes me work? Maybe we'll stay in town. So we'll maybe we'll end up eating a nice evening meal and going to a movie. Well, what if the movie is sold out? Maybe we'll buy tickets to a concert. Or, maybe I'll send my family ahead to the beach. Ok. Well, what if it rains? Maybe we'll go to the beach anyway but go to the indoor water park. What if my car breaks down? Maybe I rent a car and go to the beach. Or maybe I stay at home and watch movies and play games instead. What if I'm sick. Maybe I stay in bed or send my family ahead to the beach. Or maybe they stay home with me.

How many scenarios end up at the beach? What's the spread on the other outcomes? There's value in gaming it out. If most scenarios still end up with people going to the beach, then you have a pretty solid idea of how the weekend plays out. But if a couple of key things are changed that cause you to end up in a different place, then there's a pretty solid risk to the beach trip.

Meanwhile Billy Bob has no idea what to do when his car breaks down and his boss asks him to come in. He walks to work in the rain and gets the flu.

Anyway, this might be a terrible example. But the point is, models are imperfect and are prone to large errors out in time. Tweaking the initial state of the atmosphere and observing whether or not those tweaks cause large changes in the outcome downstream, provides a good insight as to whether or not you should have confidence in the general pattern being depicted out in time.
 
Rain Cold said:
It's essentially scenario forecasting. It's kind of like if you're planning to take your family to the beach this weekend for a nice holiday of fun in the sand. Your initial conditions are that the car works, your boss gives you the weekend off, the forecast is warm and sunny, and you are feeling good.

If you're like Billy Bob, you don't give it a second thought. But if you're like Geoffrey Von Enrich, III, you think it through. What will my weekend look like if my boss makes me work? Maybe we'll stay in town. So we'll maybe we'll end up eating a nice evening meal and going to a movie. Well, what if the movie is sold out? Maybe we'll buy tickets to a concert. Or, maybe I'll send my family ahead to the beach. Ok. Well, what if it rains? Maybe we'll go to the beach anyway but go to the indoor water park. What if my car breaks down? Maybe I rent a car and go to the beach. Or maybe I stay at home and watch movies and play games instead. What if I'm sick. Maybe I stay in bed or send my family ahead to the beach. Or maybe they stay home with me.

How many scenarios end up at the beach? What's the spread on the other outcomes? There's value in gaming it out. If most scenarios still end up with people going to the beach, then you have a pretty solid idea of how the weekend plays out. But if a couple of key things are changed that cause you to end up in a different place, then there's a pretty solid risk to the beach trip.

Meanwhile Billy Bob has no idea what to do when his car breaks down and his boss asks him to come in. He walks to work in the rain and gets the flu.

Anyway, this might be a terrible example. But the point is, models are imperfect and are prone to large errors out in time. Tweaking the initial state of the atmosphere and observing whether or not those tweaks cause large changes in the outcome downstream, provides a good insight as to whether or not you should have confidence in the general pattern being depicted out in time.
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It's a terrible example but the dang funniest thing I've read all day.... again I'm jealous.

Sent from my SM-G950U using Tapatalk
 
NCSNOW said:
Pattern has already Changed; 5 days in a row below normal at Greensboro;

-6
-6
-4
-6
-4

The days preceding this since Jan1 where all well above normal. So to me the pattern flipped January 10th. We have a few days coming up that may get 2 to 4 above normal possibly with rain, Then Monday will be much BN.
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Thank you, MJO. Any influence it had during the cold period you cited was good. However, that same MJO is now headed toward warm phases for awhile. So, the help that the MJO just gave will be replaced by an MJO whose influence would be bad with it possibly making SE ridging more stubborn. So, unless that is negated strongly enough by other factors, it will be tough to go back to a SUSTAINED cold period throughout the bulk of the SE (not just western SE) like what we just saw until the MJO at least gets out of the solid phases 4-5 that are forecasted. This will almost certainly happen within 10 days from now. So, just a little patience is needed.
 
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mrdaddyman said:
This is what I have never completely understood about ensembles. How can you load different initial conditions into an ensemble model as initial atmospheric conditions, weather observations, measurements, etc. are already measured and defined at a current point in time? It's like taking a snapshot of the current weather conditions, varying or changing them to something different, and then loading them into the ensemble. If the ensembles start out with initial conditions that are varied or possibly incorrect, how the ensembles can be expected to create an accurate forecast further out in time. Are these variations that are loaded into the ensemble being done under the assumption that the current weather conditions may not have been accurately measured or sampled and therefore may actually be incorrect to begin with?
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No model is precisely accurate, not even the ensembles. The ensembles are there to work off of to look for trends on the OP models. The physics behind the models, now that I can't explain. Think of the ensembles as a "beta" model of the OP. That's the way I think of it.
 
GaWx said:
Thank you, MJO. Any influence it had during the cold period you cited was good. However, that same MJO is now headed toward warm phases for awhile. So, the help that the MJO just gave will be replaced by an MJO whose influence would be bad with it possibly making SE ridging more stubborn. So, unless that is negated strongly enough by other factors, it will be tough to go back to a SUSTAINED cold period throughout the bulk of the SE (not just western SE) like what we just saw until the MJO at least gets out of the solid phases 4-5 that are forecasted. This will almost certainly happen within 10 days from now. So, just a little patience is needed.
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Hopefully, the amplitude will be low and NOT underestimated by the guidance like it was earlier in the year. And hopefully, it won't stall over there.
 
GaWx said:
Thank you, MJO. Any influence it had during the cold period you cited was good. However, that same MJO is now headed toward warm phases for awhile. So, the help that the MJO just gave will be replaced by an MJO whose influence would be bad with it possibly making SE ridging more stubborn. So, unless that is negated strongly enough by other factors, it will be tough to go back to a SUSTAINED cold period throughout the bulk of the SE (not just western SE) like what we just saw until the MJO at least gets out of the solid phases 4-5 that are forecasted. This will almost certainly happen within 10 days from now. So, just a little patience is needed.
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When will it become favorable again? Also, I'm assuming we can still score even in the warm phases if lower amplitude and blocking is present correct?
 
Sometimes things pop up right under your nose...case in point tomorrow AM in east TN, northeast AL and upper northwest GA. RGEM has an earlier onset of precip and has a cold bias, but the NAM and HRRR are marginally supportive wrt to 2m temps and dewpoints so its possible some areas see a light glaze of ZR if precip arrives a few hours early like the RGEM is showing. Looks spotty/showery and low qpf, plus ground temps are warm, so if it happens would be on elevated objects/surfaces.


rgem_mslp_pcpn_frzn_seus_25.png



nam3km_T2m_seus_24.png


hrrr_T2m_seus_25.png
 
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GaStorm said:
When will it become favorable again? Also, I'm assuming we can still score even in the warm phases if lower amplitude and blocking is present correct?
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Checking this further it appears we are headed into a more favorable position around 1/27 when it enters the COD.

MJO.jpg
 
CMC has the low further South a More Neutral/Positive tilt in the energy and cold press as well compared to the GFS that's why stronger backside western snow effect
 
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