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Winter 2022/23 Short/Medium Range Discussion


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1 hour ago, Baum said:

^

that can be construed as a potentially white period for some areas as has been relayed by RC, OH Weather, and Chistorm. Normal to slightly above temps during a wet period in mid-late January is hardly a deal breaker for many. Or a transition period.The Minneapolis snow train may be out to edge south and east.

I like your new pic lol

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On 1/9/2023 at 3:37 PM, michsnowfreak said:

I would actually say a warning was warranted for the conditions. I was driving in them and it was quite brutal. Most roads had snow rutted much deeper than that, lots of places were 6 to 8" or more because of blowing from in nearby fields and what not Besides think of all the advisories DTW issues for what should be warnings. At the end of the day it's just the public's warning mechanism and nothing more.  Also we really have not had much Winter rain in recent years so I can't really complain from that aspect, but I never ever want winter rain to begin with lol.

I got to stay inside and avoid the WC's all day Fri, and finally forced to venture out on Saturday when to my surprise, conditions were still actually kinda dicey in the W burbs. The "it's too bad" comment was more about getting WWA level snow, which took crazy winds carrying it into/onto the roadways to make for such bad conditions. During my 2 decades under the GRR scheme, I was always arguing for a more "conditions based" headline decision. I had so many WWA's that qualified as Warnings it was a joke. @Harry said would never happen from that office (unless it is some long-duration LES event like this November featured). That office seems to think LES is some super scary version of snow that makes roadways more slippery/difficult/dangerous when the opposite is generally true, lol.

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12 hours ago, RogueWaves said:

I got to stay inside and avoid the WC's all day Fri, and finally forced to venture out on Saturday when to my surprise, conditions were still actually kinda dicey in the W burbs. The "it's too bad" comment was more about getting WWA level snow, which took crazy winds carrying it into/onto the roadways to make for such bad conditions. During my 2 decades under the GRR scheme, I was always arguing for a more "conditions based" headline decision. I had so many WWA's that qualified as Warnings it was a joke. @Harry said would never happen from that office (unless it is some long-duration LES event like this November featured). That office seems to think LES is some super scary version of snow that makes roadways more slippery/difficult/dangerous when the opposite is generally true, lol.

First of all, I know this is way off-topic for this thread, but who's gonna put me in AMwx jail? :D

That's interesting because at IWX, they are really promoting using "impact-based messaging" and I assumed that this is the mantra NWS wide.  Maybe part of the problem is rigidity of following the criteria for meeting a particular product.

For example, at IWX the criteria for heavy snow is 3-5" for a WWA (or 2-4" at the forecaster's discretion), and greater than 6" in 12 hours or 8" in 24 hours for a Warning. In conversations I've had with their WCM, I got the impression that in the past, they may have gotten their wrist slapped for "overwarning" an event. For example, upgrading to a Winter Storm Warning for 5" of snow, even though there were exacerbating conditions such as blowing snow or glaze ice underneath the snowpack.

It seems that with impact-based forecasting, they've loosened up some and given the individual forecaster some leeway in issuing products. Just my point of view, maybe some NWS mets can chime in.

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On 1/15/2023 at 8:55 AM, IWXwx said:

First of all, I know this is way off-topic for this thread, but who's gonna put me in AMwx jail? :D

That's interesting because at IWX, they are really promoting using "impact-based messaging" and I assumed that this is the mantra NWS wide.  Maybe part of the problem is rigidity of following the criteria for meeting a particular product.

For example, at IWX the criteria for heavy snow is 3-5" for a WWA (or 2-4" at the forecaster's discretion), and greater than 6" in 12 hours or 8" in 24 hours for a Warning. In conversations I've had with their WCM, I got the impression that in the past, they may have gotten their wrist slapped for "overwarning" an event. For example, upgrading to a Winter Storm Warning for 5" of snow, even though there were exacerbating conditions such as blowing snow or glaze ice underneath the snowpack.

It seems that with impact-based forecasting, they've loosened up some and given the individual forecaster some leeway in issuing products. Just my point of view, maybe some NWS mets can chime in.

Sure. I believe the agency as a whole is pushing to highlight the impacts of winter weather more...you see this with the recent emphasis on snow squalls, with products such as WSSI that give impacts for more than just total snowfall, and in training I recently went through regarding winter weather stuff I got the impression that they wanted impacts to be considered when issuing winter weather headlines. 

However, there are still a lot of different individual forecaster opinions along with varying philosophies from office to office. I can say from a verification standpoint, warnings are verified based on what gets put into Stormdata. Basically, warning level events or events resulting in fatalities are supposed to be entered. So if there's no warning out covering an event entered, the event was missed. If there is a warning out and no event gets entered into Stormdata, the warning is a false alarm. It makes it very hard for offices to "massage" the numbers (I don't necessarily mean cook the books so much as leaning a certain way if it's "close" based on what headlines were out...basically, less room to give yourself a buffer, which I don't think is the best when verifying a forecast). Some offices (including mine) are big on consistent Stormdata entries. If similar events have been written into Stormdata before they should continue to be entered...and vice versa if similar events haven't traditionally made Stormdata. We have a clause here that winter wx headlines can be issued based on impact, but when we verify it in Stormdata we need tangible evidence of "impact" from a given forecast zone...high standards to get included if amounts are sub-criteria...so, for us to go with the "impact based" headline (especially warnings...advisories can be a little looser) we need to be pretty sure that the aggravating factors will be significant. In the case of the December 23rd storm, at least in the CLE CWA, that was the case and everyone issued warnings. 

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Sure. I believe the agency as a whole is pushing to highlight the impacts of winter weather more...you see this with the recent emphasis on snow squalls, with products such as WSSI that give impacts for more than just total snowfall, and in training I recently went through regarding winter weather stuff I got the impression that they wanted impacts to be considered when issuing winter weather headlines. 
However, there are still a lot of different individual forecaster opinions along with varying philosophies from office to office. I can say from a verification standpoint, warnings are verified based on what gets put into Stormdata. Basically, warning level events or events resulting in fatalities are supposed to be entered. So if there's no warning out covering an event entered, the event was missed. If there is a warning out and no event gets entered into Stormdata, the warning is a false alarm. It makes it very hard for office's to "massage" the numbers (I don't necessarily mean cook the books so much as leaning a certain way if it's "close" based on what headlines were out...basically, less room to give yourself a buffer, which I don't think is the best when verifying a forecast). Some offices (including mine) are big on consistent Stormdata entries. If a similar events have been written into Stormdata before they should continue to be entered...and vice versa if similar events haven't traditionally made Stormdata. We have a clause here that winter wx headlines can be issued based on impact, but when we verify it in Stormdata we need tangible evidence of "impact" from a given forecast zone...high standards to get included if amounts are sub-criteria...so, for us to go with the "impact based" headline (especially warnings...advisories can be a little looser) we need to be pretty sure that the aggravating factors will be significant. In the case of the December 23rd storm, at least in the CLE CWA, that was the case and everyone issued warnings. 
The pre-Christmas storm is definitely an example of impact based vs. criteria based WSW. We had that leeway in the past depending on the event, but it's gone more down that road. I'd say more often than not we still try to hold to issuing warnings for heavy snow with the 6"/8 hour and 8"/12 hour criteria in mind. Pre-Christmas was a special case because the combined impacts of blowing snow, high winds, and cold were fairly high end for the little snow we had.

Even though advisories are supposed to go away in a few years, we've definitely trended even more impact based for advisories. The thinking is that is there much difference between 2" of snow causing snow covered roads vs. 4" causing snow covered roads. The traditional 3-5" criteria probably was a holdover from the snow advisory when WWAs grouped in the various hazards that used to have their own advisories.

WSSI is an advancement in terms of impacts that would help reduce the subjectivity. We noted that it ran a bit hot the first few years, especially higher on the impact scale. An example is the Feb 1-3, 2022 event having top end "Extreme" impacts forecast south of I-80. It was definitely a solid winter storm, but not extreme if you scale it to truly historic events like GHD I and upper echelon storms like GHD II.

Some recalibration was done this winter to help with that. The hope is that it can be of more assistance in issuing Winter Storm Watches and Warnings in the future. There's also probabilistic WSSI in development as part of this process.


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14 minutes ago, RCNYILWX said:

The pre-Christmas storm is definitely an example of impact based vs. criteria based WSW. We had that leeway in the past depending on the event, but it's gone more down that road. I'd say more often than not we still try to hold to issuing warnings for heavy snow with the 6"/8 hour and 8"/12 hour criteria in mind. Pre-Christmas was a special case because the combined impacts of blowing snow, high winds, and cold were fairly high end for the little snow we had.

Even though advisories are supposed to go away in a few years, we've definitely trended even more impact based for advisories. The thinking is that is there much difference between 2" of snow causing snow covered roads vs. 4" causing snow covered roads. The traditional 3-5" criteria probably was a holdover from the snow advisory when WWAs grouped in the various hazards that used to have their own advisories.

WSSI is an advancement in terms of impacts that would help reduce the subjectivity. We noted that it ran a bit hot the first few years, especially higher on the impact scale. An example is the Feb 1-3, 2022 event having top end "Extreme" impacts forecast south of I-80. It was definitely a solid winter storm, but not extreme if you scale it to truly historic events like GHD I and upper echelon storms like GHD II.

Some recalibration was done this winter to help with that. The hope is that it can be of more assistance in issuing Winter Storm Watches and Warnings in the future. There's also probabilistic WSSI in development as part of this process.

 

I suspect when advisories go away we'll see a bit more of a shift towards the "impact-based" paradigm, as when we only have the warning headline we may have to issue warnings when we think an event will be high impact, regardless of if it hits criteria. I'm curious to see if what becomes of advisories (the broad "plain language statements") are issued more like today's special weather statement, a soft headline that technically isn't a watch/warning product, which may also allow for more impact-based considerations. I've never loved having a set snow criteria for advisories, because as you said there are many other variables that can make a given amount of snow higher or lower impact. 

Am hoping for more synoptic winter storms to test out the tweaked WSSI this winter...this isn't a bad look if it's correct:

859187300_GEFS500.thumb.png.74f733a3f8656b1e4fd532818c91f7f7.png

368287043_EPS500.thumb.png.53e580a0ec7081cfa26b532dc0e2a3bf.png

I think the western ridge is legit, but we'll see if we get that subtle little -NAO that can help push the PV south over Hudson Bay, which would get all of the subforum cold enough for snow in late January. 

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Thanks for the input. It really brings to light some of the factors that goes into issuing products. It will be interesting to see how it affects forecast wording when advisories finally drop.

Sorry to completely derail the thread. Now back to your regularly scheduled short/medium range discussion which looks to be more interesting next week.

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I suspect when advisories go away we'll see a bit more of a shift towards the "impact-based" paradigm, as when we only have the warning headline we may have to issue warnings when we think an event will be high impact, regardless of if it hits criteria. I'm curious to see if what becomes of advisories (the broad "plain language statements") are issued more like today's special weather statement, a soft headline that technically isn't a watch/warning product, which may also allow for more impact-based considerations. I've never loved having a set snow criteria for advisories, because as you said there are many other variables that can make a given amount of snow higher or lower impact. 
Am hoping for more synoptic winter storms to test out the tweaked WSSI this winter...this isn't a bad look if it's correct:
859187300_GEFS500.thumb.png.74f733a3f8656b1e4fd532818c91f7f7.png
368287043_EPS500.thumb.png.53e580a0ec7081cfa26b532dc0e2a3bf.png
I think the western ridge is legit, but we'll see if we get that subtle little -NAO that can help push the PV south over Hudson Bay, which would get all of the subforum cold enough for snow in late January. 
I'm definitely not a fan of getting rid of advisories - supposedly surveys showed a majority were confused by them because to your point, what is a winter weather statement? What do the TV Mets message on their broadcasts - a winter weather statement is in effect? That is an interesting point though that getting rid of advisories may pave the way to issuing more purely impact driven warnings.

Upcoming pattern continues to look solid for fairly regular chances - as long as the mean troughing stays biased west, but with TPV near Hudson Bay, it keeps everyone in the game. No guarantees, and this has certainly been a bad winter for snow enthusasiasts outside of MSP and the LES belts, but would be surprised if there's no widespread decent events in snow starved areas from this weekend through mid Feb.

Sent from my SM-G998U using Tapatalk

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