Typhoon Tip Posted January 15, 2018 Author Share Posted January 15, 2018 It's hard to say what form the synoptic future will take. The GEFs tele's continue to elaborately put up a spread signaling a pattern supporting warmth, with an indeterminate end date... However, there are weak countermanding signals: such as a persistent lower the NAO; as well ...the general tenor of the operational guidance et al, not really exercising the rights given to them by their ensemble means (particularly in the GFS family) to expand the warm look as much as they could. In a holistic, ... less than scientific appeal, one can almost 'feel' the operational GFS in particular, doing everything physically imaginable to fight its own ensemble argument. Routinely, ...cycle after cycle features a complexions that are cooler relative to this: The 06z is a fantastic example of having pretty much no idea what it's ensemble mean wants to do with the next ten days to two weeks. I think it even has a grid concerning mix bomb out there at first glance... Meanwhile, that spread above...with a total -6 SD correction of the PNA while the EPO "big-brother" torments above 0, means it's open season on Chinook/Pac sweeps to the EC...and probably crockus shoots and greening lawns. The rub is ... the PNA is a truly huge domain space? It covers like 1/8th the planetary surface area in terms of raw coordinates. The operational GFS could still "fit" inside that appeal above, ...though barely.. given to idiosyncrasies within, and still have those numerical equivalence/modes be true. If that were not enough.. the CPC has a significant PNA mode flipping back positive with every member (rare to get that much agreement that far in advance) heading toward Feb 1st. It's a newly emergent signal out there at the end of oblivion ...so obviously subject to change. I'm curious if there are any roll-forward analogs for modest La Nina an AGW denial - ha Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 Does anyone know any good references for estimating ice storm damage from ice accretion/freezing rain accumulation? I can't seem to find anything specific on estimating how much accretion will be effective for a given amount of zr. Link to comment Share on other sites More sharing options...
wx2fish Posted January 15, 2018 Share Posted January 15, 2018 Nice backdoor on Monday across CNE and NNE on the Euro Link to comment Share on other sites More sharing options...
weathafella Posted January 15, 2018 Share Posted January 15, 2018 6 minutes ago, wx2fish said: Nice backdoor on Monday across CNE and NNE on the Euro That hp in eastern Canada could easily change ideas even down in SNE. Link to comment Share on other sites More sharing options...
eyewall Posted January 15, 2018 Share Posted January 15, 2018 2 hours ago, OSUmetstud said: Does anyone know any good references for estimating ice storm damage from ice accretion/freezing rain accumulation? I can't seem to find anything specific on estimating how much accretion will be effective for a given amount of zr. Yeah I have always wanted to see information on this as well. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted January 15, 2018 Share Posted January 15, 2018 7 minutes ago, weathafella said: That hp in eastern Canada could easily change ideas even down in SNE. Has the look of dooring down to NYC Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 Just now, eyewall said: Yeah I have always wanted to see information on this as well. https://link.springer.com/content/pdf/10.1007%2Fs11434-011-4868-2.pdf https://www.researchgate.net/publication/235110898_Ice_Accretion_in_Freezing_Rain I found these two and a few others, but it's still not an easy answer. It appears raindrop size also plays a role in ice loading. Link to comment Share on other sites More sharing options...
eyewall Posted January 15, 2018 Share Posted January 15, 2018 Just now, OSUmetstud said: https://link.springer.com/content/pdf/10.1007%2Fs11434-011-4868-2.pdf https://www.researchgate.net/publication/235110898_Ice_Accretion_in_Freezing_Rain I found these two and a few others, but it's still not an easy answer. It appears raindrop size also plays a role in ice loading. That would make sense on how much runs off as liquid. I would imagine it is much easier for smaller drops to freeze more completely than large rain drops. Link to comment Share on other sites More sharing options...
ORH_wxman Posted January 15, 2018 Share Posted January 15, 2018 34 minutes ago, wx2fish said: Nice backdoor on Monday across CNE and NNE on the Euro Yeah not looking so torchy all of the sudden if we get that synoptic setup. Link to comment Share on other sites More sharing options...
OceanStWx Posted January 15, 2018 Share Posted January 15, 2018 2 hours ago, OSUmetstud said: Does anyone know any good references for estimating ice storm damage from ice accretion/freezing rain accumulation? I can't seem to find anything specific on estimating how much accretion will be effective for a given amount of zr. Not sure if you'll be able to see this or if it's behind our firewall: FRAM That's the model that we're moving towards for ice accumulation grids. You can see from some of the background research though, that 70% of the rain rate is typically a good estimate for most rainfall rates. Once you head towards heavy rain rates the efficiency falls to closer to 50%. But then wind can help not only transport heat away, but increase the likelihood that drops hit a surface (as they fall sideways instead of straight down), like 2008. The other tools seem to have a high bias. 1:1 for obvious reasons, but CRREL also had a high bias because it doesn't account for latent heating. It also had a fairly extreme bias with strong winds (like high terrain winds) where you could end up with more ice than actual QPF. No of course FRAM is flat surface (deck, car, etc), so to covert to power lines or tree branch it is about 35-40% of the FRAM amount. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted January 15, 2018 Share Posted January 15, 2018 4 hours ago, Hoth said: Amazing considering the torch a few days ago. No kidding.. Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 40 minutes ago, OceanStWx said: Not sure if you'll be able to see this or if it's behind our firewall: FRAM That's the model that we're moving towards for ice accumulation grids. You can see from some of the background research though, that 70% of the rain rate is typically a good estimate for most rainfall rates. Once you head towards heavy rain rates the efficiency falls to closer to 50%. But then wind can help not only transport heat away, but increase the likelihood that drops hit a surface (as they fall sideways instead of straight down), like 2008. The other tools seem to have a high bias. 1:1 for obvious reasons, but CRREL also had a high bias because it doesn't account for latent heating. It also had a fairly extreme bias with strong winds (like high terrain winds) where you could end up with more ice than actual QPF. No of course FRAM is flat surface (deck, car, etc), so to covert to power lines or tree branch it is about 35-40% of the FRAM amount. this is great. Thank you. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted January 15, 2018 Share Posted January 15, 2018 9 hours ago, CoastalWx said: Yeah well looks kind of meh going forward to me. I don't like seeing blues at H5 from AK through CA. Blech. I'm fine with it..that was expected to happen mid season. I'm pretty confident the nice look comes back later in Feb and into March. Doesn't mean we can't snow in the mean time... Link to comment Share on other sites More sharing options...
OceanStWx Posted January 15, 2018 Share Posted January 15, 2018 2 minutes ago, OSUmetstud said: this is great. Thank you. No problem. I have a soft spot for ice. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted January 15, 2018 Share Posted January 15, 2018 I just think protracted stretches of harsh winter are done for awhile. Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 2 minutes ago, OceanStWx said: No problem. I have a soft spot for ice. lol me too. Disasters of all kinds. Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 how do you combine the three methods to get one number? 12 minutes ago, OceanStWx said: No problem. I have a soft spot for ice. Link to comment Share on other sites More sharing options...
OceanStWx Posted January 15, 2018 Share Posted January 15, 2018 Just now, OSUmetstud said: how do you combine the three methods to get one number? Our go to is FRAM only now. If we truly hated the output, we could alternatively use a straight slider ratio of QPF to ice, or use the CRREL model. Link to comment Share on other sites More sharing options...
OSUmetstud Posted January 15, 2018 Share Posted January 15, 2018 27 minutes ago, OceanStWx said: Our go to is FRAM only now. If we truly hated the output, we could alternatively use a straight slider ratio of QPF to ice, or use the CRREL model. ahh nice. We kinda have an interesting situation tomorrow, heavy rates, but cold with lower wet bulb and plenty of wind. I Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 15, 2018 Author Share Posted January 15, 2018 It's a warmer than normal pattern .... backdoor front or not. In fact, you could almost argue that a BD is required in a warmer than normal pattern - counter intuitive perhaps, but the pattern and the phenomenon are obviously connected. I suppose it is true that a BD air mass could get deep enough to turn into a bona fide CAD icer/mix ...but the pattern is still warmer than normal. As New England winter enthusiasts, we get the benefit of 'enabling' our fantasies do to the local geography 'cheating' the warm air with this tucking thing that happens at pretty much all scale (actually). Link to comment Share on other sites More sharing options...
weathafella Posted January 15, 2018 Share Posted January 15, 2018 Just now, Typhoon Tip said: It's a warmer than normal pattern .... backdoor front or not. In fact, you could almost argue that a BD is required in a warmer than normal pattern - counter intuitive perhaps, but the pattern and the phenomenon are obviously connected. I suppose it is true that a BD air mass could get deep enough to turn into a bona fide CAD icer/mix ...but the pattern is still warmer than normal. As New England winter enthusiasts, we get the benefit of 'enabling' our fantasies do to the local geography 'cheating' the warm air with this tucking thing that happens at pretty much all scale (actually). But oh do rue this advantage in spring! Link to comment Share on other sites More sharing options...
OceanStWx Posted January 15, 2018 Share Posted January 15, 2018 1 hour ago, OSUmetstud said: ahh nice. We kinda have an interesting situation tomorrow, heavy rates, but cold with lower wet bulb and plenty of wind. I Nice 20 knot easterly wind there. Certainly looks like a nasty forecast sounding anyway. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted January 15, 2018 Share Posted January 15, 2018 Weeklies are hideous thru week 4, but as bad as they’ve been all winter, who cares Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted January 15, 2018 Share Posted January 15, 2018 3 minutes ago, Damage In Tolland said: Weeklies are hideous thru week 4, but as bad as they’ve been all winter, who cares Seems to be the kind of winter where we take advantage if every little opening...even during a general relaxation...such as Wednesday. Bodes well. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted January 15, 2018 Share Posted January 15, 2018 4 minutes ago, 40/70 Benchmark said: Seems to be the kind of winter where we take advantage if every little opening...even during a general relaxation...such as Wednesday. Bodes well. Well if you want your forecast to verify, and I think you do since it’s referenced frequently , you wouldn’t think the look of the weeklies bodes well. Link to comment Share on other sites More sharing options...
LurkerBoy Posted January 15, 2018 Share Posted January 15, 2018 13 minutes ago, Damage In Tolland said: Weeklies are hideous thru week 4, but as bad as they’ve been all winter, who cares Define “hideous” plz? Link to comment Share on other sites More sharing options...
CoastalWx Posted January 16, 2018 Share Posted January 16, 2018 I didn’t think it was terrible. Week 3 was kind of ugly but week 4 looked decent with riding in AK and Greenland. Week 3 if anything slightly improved. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted January 16, 2018 Share Posted January 16, 2018 Uh oh Link to comment Share on other sites More sharing options...
RUNNAWAYICEBERG Posted January 16, 2018 Share Posted January 16, 2018 5 minutes ago, CoastalWx said: I didn’t think it was terrible. Week 3 was kind of ugly but week 4 looked decent with riding in AK and Greenland. Week 3 if anything slightly improved. Referencing models correctly is in the eye of the beholder. 26 minutes ago, LurkerBoy said: Define “hideous” plz? Subtract 8 from the DIT index. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted January 16, 2018 Share Posted January 16, 2018 35 minutes ago, Damage In Tolland said: Well if you want your forecast to verify, and I think you do since it’s referenced frequently , you wouldn’t think the look of the weeklies bodes well. I expected a general relaxation into at least mid Feb. Link to comment Share on other sites More sharing options...
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