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Post by ndolan387 on Apr 8, 2020 20:31:38 GMT -6
My guess is 36* Friday AM at STL You thinking the wind is going to keep temps up? I'm thinking closer to freezing with h85 around -6*C or so. But I could see us staying a bit warmer if we stay downstream of the ridge axis. There could be a little mixing Fri morning, but winds look to be around 5 mph or less. I agree Coz, the C high is too far west. Another thing to take into account is we have less nighttime to have radiational cooling. Less than 12 hrs. Though I agree, based upon those 850mb temps, 32-34 seems doable. We may have a better shot to go before freezing AM Mon. Or AM Tues when winds are supposed to be calm.
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Post by ndolan387 on Mar 23, 2020 20:42:29 GMT -6
Those were some of, if not the biggest snowflakes (monster hamsters) I have witnessed in my life yesterday!
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Post by ndolan387 on Mar 21, 2020 8:24:19 GMT -6
What model website do you use for isentropic features? I believe Dr. Graves has potential temperature features (290-310 K) on the CIPS model guidance. I don't look at constant potential temperature, density surface features, but I should more. For Sun morning, 850mb and 700mb winds are southerly showing clear WAA. www.wxcaster.com/isentropic.htmCool, thanks!
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Post by ndolan387 on Mar 20, 2020 22:13:11 GMT -6
The 18z NAM looks decent at 500mb for early Sun. A nice little neg tilt ripple to the west of us as we are in the region where cyclonic vorticity is being advected toward. The big issue is 850mb temps aren't cold enough. Still think we will see some some snowflakes Sun morning which I'll take before it changes over to all rain. It's going to be close...especially up here. This kind of caught me by surprise but I think we could see some minor accums. up this way before it turns over...but that will be dependent on the timing. It looks good in the mid-levels with good isentropic ascent and large scale lift/DPVA...and definetely cold enough at 700mb unlike the last system. NAM also brings down an area of status off the lakes which keeps overnight temps near the river valley up around freezing...hopefully that's the case. What model website do you use for isentropic features? I believe Dr. Graves has potential temperature features (290-310 K) on the CIPS model guidance. I don't look at constant potential temperature, density surface features, but I should more. For Sun morning, 850mb and 700mb winds are southerly showing clear WAA.
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Post by ndolan387 on Mar 20, 2020 22:03:18 GMT -6
Also keeping in mind that the NAM has displayed a warm bias as of late...but the cooler mid-levels and good lift make me think snow could break out until diurnal warming and WAA takes over. Yeah up in Brighton, 850mb temps will be colder so you will have more snow time! We have a chance here for an hour or two of WAA snow, but it looks more borderline across the immediate metro.. Maybe it will trend colder.
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Post by ndolan387 on Mar 20, 2020 16:35:49 GMT -6
The 18z NAM looks decent at 500mb for early Sun. A nice little neg tilt ripple to the west of us as we are in the region where cyclonic vorticity is being advected toward. The big issue is 850mb temps aren't cold enough. Still think we will see some some snowflakes Sun morning which I'll take before it changes over to all rain.
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Post by ndolan387 on Mar 15, 2020 9:09:40 GMT -6
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Post by ndolan387 on Mar 9, 2020 20:18:12 GMT -6
The SPC doesn't seem to jazzed about the severe weather potential on Thurs, but we are still a little under 3 days out. There's still some wiggle room for the mesoscale ingredients to change a little. Moving on, yeah that's a nice negative tilt little ripple in the upper level flow for Fri into Sat. A quick hit of wet snow Sat evening. Very marginal setup and the ripple looks to enter and leave our region very quickly! Not much to write home about other than it's the atmosphere reminding us winter isn't done.
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Post by ndolan387 on Mar 3, 2020 10:02:45 GMT -6
Why are they testing the sirens again today? Due to Nashville's tornado??
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Post by ndolan387 on Feb 26, 2020 21:04:59 GMT -6
Driving home from work today after 5pm towards 6pm was crazy...it got dark as I was going W on I-64. I was confused at what it was, but then I was like this is a rain/snow squall. It started snowing some as I drove through the Chesterfield Valley. It reminded me of a spring time thunderstorm (which it's but snow). It looked like north in St. Charles County is where it snowed at a faster rate. Good call Snowstorm920, Unclesam, and Btrn! The HRRR was picking up on the convective nature with the snow squalls. I wish I had more time to contribute to this board.
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Post by ndolan387 on Feb 26, 2020 8:49:01 GMT -6
1.25" in Northern Wildwood.
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Post by ndolan387 on Feb 24, 2020 22:08:18 GMT -6
Credit given to Btrn! That negative tilt is nice as the heights fall and become enclosed. As well, better lift through the DGZ. The 00z NAM was definitely a slam dunk run. Can't put all our eggs in one basket/model run, but the consensus is growing for better deformation snow. The 00z GFS looks decent in the upper levels. It looks like the SREF plumes have a mean of 1.26" for the KSTL up from 1.14" this afternoon.
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Post by ndolan387 on Feb 24, 2020 13:01:51 GMT -6
This isn't an 8-12" storm anywhere, IMO...been seeing some big numbers being put out that are unrealistic. I can't remember over the last 5 years when TWC was right or somewhat accurate with a snowstorm forecast.
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Post by ndolan387 on Feb 23, 2020 22:32:14 GMT -6
A nice negative tilt on the 500mb flow for Tues-Wed. Steep lapse rates and cyclonic flow...although omega doesn't look that great. Looks like whatever mood setting you want snow. Otherwise, the pattern into the first 10 days (really later on too) of March looks ripe for a snowstorm.
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Post by ndolan387 on Feb 20, 2020 22:36:02 GMT -6
Need that trough to go negative a bit sooner on the GFS. It goes negative overhead. Would be nice to get it to go negative to our west Agree...need a negative tilt sooner by around 200 mi to slow the system. Now that's a western Great Lakes bomb haha.
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Post by ndolan387 on Feb 20, 2020 22:13:40 GMT -6
The front wave with our rainer Sun/Mon looks to be pretty weak. Moving on, one thing that's becoming increasingly confident is that the late Tues system will be propagating to the east quickly. The 250mb low (associated North of the main jet streak down in the Southeast) moves around 300 mi (from IL/IN border to Cleveland) in 12ish hours on the 00z GFS. During that track, we have some upper level divergence to provide some lift. Though then, we are in the confluence zone...in between the entrance and exit regions then convergence zone as it moves to the east. We need the energy to slow down and mature more in order to get the right phase. It doesn't acquire a TROWAL until entering the Great Lakes region.
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Post by ndolan387 on Feb 19, 2020 22:55:33 GMT -6
And the NAO looks to finally go negative at the same time.
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Post by ndolan387 on Feb 19, 2020 22:00:25 GMT -6
Mid to late next week I think still has potential for a snowstorm. We shouldn't have to worry about our cold air supply. Just need the right phase as others have mentioned. It's the best potential this winter besides the mid Dec storm.
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Post by ndolan387 on Feb 18, 2020 21:43:34 GMT -6
Hey WSC, this was the march snowstorm that brought St. Charles thundersnow right? /photo/1 I think that was the storm with an extremely narrow band of heavy snow. It wasn’t modeled like that, so many were freaking out lol. BRTN frequently mentions it as some of the heaviest snow he has seen. St. Charles got in on the band for a couple hours and picked up close to 6 inches. I don’t recall thunder snow, but it was 12 years ago. Palm Sunday was cooler in St. Charles. I had close to 18 inches of snow Palm Sunday...14" of heavy wet snow in Northern Wildwood!! March 24, 2013.
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Post by ndolan387 on Feb 17, 2020 19:54:12 GMT -6
First true zonal pattern in the upper levels and surface in a while. All it takes is a shortwave to bring us a bone. Usually the shortwaves aren't modeled well until soon before their delivering.
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Post by ndolan387 on Feb 16, 2020 9:18:10 GMT -6
The models are well, all yawn. But, I believe it’s premature to take snow removal equipment off of vehicles. After near record high AOs almost all winter and an EPO that’s been near record highs as well, what goes up must come down. That could very well happen in late Feb/early March. However, my prediction for February hasn’t come to fruition so that gives less confidence for this one as well. I think seeing more cold air available looks promising to me. Emphasis on a bookend winter even tho we had some non rain lower impact events in between.
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Post by ndolan387 on Feb 16, 2020 9:11:44 GMT -6
AO and NAO both look to crash late month. I think winter has one more last hurrah atleast I totally agree...AO and NAO are going to crash eventually it's only a matter of time. Maddogchief and others have talked about how the teleconnections change so quickly with each update tho so it's hard to pinpoint when.
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Post by ndolan387 on Feb 15, 2020 11:41:21 GMT -6
Some cool looking clouds out there this morning. Almost look like mini mammantus clouds Yeah from what I saw, I thought they were mammatus clouds. Very cool for mid Feb as these are associated usually with outflow boundaries!
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Post by ndolan387 on Feb 14, 2020 12:10:42 GMT -6
Yeah winds resided overnight, but the speed didn't get below 3-5 mph till after sunrise. The positioning of the high is so crucial in this type of situation. So realistically speaking, IF the high progressed further SE and IF we had >1" of snow which was possible then lows this morning would of been -4F to -6*F. But, we don't live in a world of what ifs haha!
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Post by ndolan387 on Feb 13, 2020 20:22:43 GMT -6
Interesting tidbit from the NWS disco this afternoon... Cool how the upper level trough resulted in cyclonic flow aided with lift to produce the snow steamers! I would say widespread across the area besides maybe KSTL haha will go below zero by tomorrow morning!
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Post by ndolan387 on Feb 12, 2020 21:22:09 GMT -6
I'm thinking we will see 1-1.5" along 44 in mo and 64 in IL. The DGZ dries out tho as the event unfolds even tho the models depict decent lift through the DGZ. No way ratios are 7/8-1. That's really nice. Did you calculate with the cobb method? I assume you are just eyeballing based the saturation location, temperature profile, and omega.
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Post by ndolan387 on Feb 12, 2020 17:15:32 GMT -6
The models have converged on a 2 hour hit of moderate snow tonight between 11-2am in the metro. We actually might pick up 0.15" qpf but ratios are shyt I had assumed ratios would be pretty good tonight...guess that's not the case? Yeah I would have thought the same thing...decent ratios above 12 to 1. But the more I look at the evolution of the deformation snows after midnight, it looks mostly like a katafront. Which is when the (precipitation) snow occurs before the Arctic air's CAA really starts spilling into our area. The biggest impact as we have stated for Thurs morning's rush is the flash freezing. Also, if we get more than inch...we will have a good chance to get down to 0* Fri morning! WCs -5 to -15!!
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Post by ndolan387 on Feb 11, 2020 21:54:18 GMT -6
I saw Luke as the first name so I didn't know for sure haha.
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Post by ndolan387 on Feb 11, 2020 21:46:05 GMT -6
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Post by ndolan387 on Feb 9, 2020 22:26:23 GMT -6
If the NAM is right the storm after midnight Tues to later Wednesday will be moving to the NE in a hurry. The 250mb jet streak maximum winds reach 200+ kts. The storm could get caught up in the upper level jet streak. It could be similar to what happened this past Wednesday when our moisture supply shut down around 6 hrs earlier than what's modeled. So it most likely won't be a long duration storm.
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