HSVweather
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No changeover as expected on the backside here. It did drop from 50 at 0430 to 35 now. Clear skies back in MS/AR. Is the next energy to watch the back in Kansas currently?
So by get the job done I’m still confused with what we’re taking about here. Flurries or are you saying epic convective snow bursts with decent to heavy rates? Sounds like you’re kinda bullish here. If you were to forecast the event, what’s the most likely outcome?
Most likely outcome, if/where it snows it’s probably not going to be just some flurries. Near Absolutely unstable soundings/steep low level lapse rates with saturated DGZ, that’s a highly convective environment. Thus, if it snows, it will come down pretty hard imo based on that and we will have mini snow squalls where precip is legitimately falling. The low levels become unsaturated with the heating of the day and without it we won’t be unstable enough to generate precipSo by get the job done I’m still confused with what we’re taking about here. Flurries or are you saying epic convective snow bursts with decent to heavy rates? Sounds like you’re kinda bullish here. If you were to forecast the event, what’s the most likely outcome?
Most likely outcome, if/where it snows it’s probably not going to be just some flurries. Near Absolutely unstable soundings/steep low level lapse rates with saturated DGZ, that’s a highly convective environment. Thus, if it snows, it will come down pretty hard imo based on that and we will have mini snow squalls where precip is legitimately falling. The low levels become unsaturated with the heating of the day and without it we won’t be unstable enough to generate precip
What I’m actually saying is that your concerns about low level dry air on the HRRR are unfounded based on my last few responses to you. 60% RH in a convective environment is not that big of a deal esp when your dry layer is only just over a few thousand feet thick
I imagine in this instance there would probably be a little little bit at the beginning, then it would get windy then boom burst of snowSo no virga and instant snow bursts. We’ll see!
I imagine in this instance there would probably be a little bit at the beginning, then it would get windy then boom burst of snow
No need to get snarky and have an attitude here because I disagree with you. Your concern is based on the HRRR sounding you were gawking over last night and that dry layer wasn’t that strong or very deep at all, unless you can convince me that a 3-4K feet dry layer with 80% RH is substantial I don’t see your argument. Anyway carry on.If there’s any virga whatsoever than my concern about a dry layer isn’t “unfounded”
What some models are showing for the backside snow as main line passes thru GA around 2-3 PM there is some moisture kick-in that fills in from SW/NE along back of line and it appears that would be what has potential to changeover in the afternoon hours.
No need to get snarky and have an attitude here because I disagree with you. Your concern is based on the HRRR sounding you were gawking over last night and that dry layer wasn’t that strong or very deep at all, unless you can convince me that a 3-4K feet dry layer with 80% RH is substantial I don’t see your argument. Anyway carry on.
So what does this front moving faster than anticipated mean for the snow in Georgia and/or possibility of convective snow east of the mountains?
I don’t recall saying substantial, maybe I did, but it’s there nonetheless. My point was to keep expectations low. You aren’t exactly the nicest with wording on here, (and maybe that’s 100% unintentional on your part and it’s how I take it), but thanks for your input. I do appreciate you answering my questions.
FFC mentioned the models are still showing moisture redeveloping.It really only affects GA and it's potential for backend snow on the main band coming through our area right now. Doesn't really affect the snow flurry/shower potential afterwards.
I still Managed a light rain snow mix with that November 29th trough to ?This event on Nov 30th in the St Louis metro area probably isn't a bad, conservative analog to what we'll see tomorrow in the Carolinas (& most NWP models never forecasted even so much as a flurry in their forecast fields, most places saw at least flurries.), although this trough and associated cyclonic vorticity advection is much, much stronger this time around than it was for STL on Nov 30. Both of these generally argue for better coverage of precipitation and higher rates where precipitation occurs tomorrow in the Carolinas vs in STL on Nov 30 imo.
Nov 30 event
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Tomorrow
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The lower levels aren’t dry though in that sounding, if you looked at the corresponding sounding from pivotal weather, the lower level relative humidity is still greater than 80%, with a sub saturated layer that’s only 3000-4000 feet deep verbatim on the HRRR, that’s a pretty negligible dry layer if you ask me. Yes saturation with respect to ice is an additional percent or two lower than water which gives additional one or two RH percentage points in a sub freezing environment. If the HRRR came to fruition there wouldn’t be any concerns with dry air imo based on that sounding you showed. Oth, other models like the NSSL, ARW, & NAM are drier with a shallower mixed layer and they do look more concerning in that regard and I think the HRRR may be over mixing the BL which is causing it to produce more precip than the other cams. For ex: Simply mixing two relatively moist but unsaturated parcels leads to supersaturation because the mixing occurs linearly while saturation vapor pressure is exponential. Excess boundary layer mixing begets saturation and forcing for ascent
Looks like that may be happening with the line developing on the east side of BHM.It looks like as the trough goes neutral, another small piece of energy gets injected into main energy of the upper level trough which allows some moisture to redevelop on the backside of the band. That being said, NWS just put out a tweet saying the line is moving 1-2 hours faster than their modeling so that may not bold well for any chance of snow on the backside of the band.
Many years back, we had some convective snow bands come through the day after a storm. It was very impressive. It would darken up, snow (big flakes) for 20 minutes, stop, and then the sun would come out. It did this three or four times.
Im def interested in there next update especially the implications of the precip stalling/slowing down this evening. The wienie in me wants the precip to hang around longer to get the cold air to catch up....GSP hinted in their latest discussion that small pops might be needed east of the mountains for tomorrow.
Sure is..nothing fell in NW Ala this morning when radar showed a good area of snowIf there’s any virga whatsoever than my concern about a dry layer isn’t “unfounded”
Looks similar to this storm
All virga apparentlyAlso, this band is most likely virga but it is visible to some degree on all three of the closest radar sites (however it is also pretty far from those three sites). I’d still be interested to see if anything is making it to the ground.
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