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Northern Plains Discussion


prinsburg_wx

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A lot of buzz up here about this system. Its interesting to see how the models have evolved over time. About a week ago it seemed like the GFS was the only real model showing a snowy possibility until the NAM ramped up yesterday and at that point the GFS basically looked boring. Now everything seems to be shifting towards a consensus and it seems like there will be an event. How big of an event remains to be seen, but I do have a hard time believing some of the crazier totals some models have shown over the past day and a half (current NAM runs and earlier Euro runs).

It does seem a bit strange that such an intense deformation band could form at this time of year and I also wonder where the moisture is coming from. Jim brought up a good point about the Great Lakes still being fairly warm and I am guessing that is where the majority of the moisture is coming from. If a band does form as depicted by the NAM and earlier Euro runs, obviously everything will be dependent on the track.

My guess at this point is that GFK could see 2-4 inches (and that is on the high side to me... at least at the moment) with northern MN and points north (Lake of the Woods area) getting a pretty hefty dose. I'm so used to systems like this from living in the southeast (temps borderline... changeover characteristics... optimal low path). Didn't think we would have one so hard to forecast up here in the great cold north! Lol.

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A lot of buzz up here about this system. Its interesting to see how the models have evolved over time. About a week ago it seemed like the GFS was the only real model showing a snowy possibility until the NAM ramped up yesterday and at that point the GFS basically looked boring. Now everything seems to be shifting towards a consensus and it seems like there will be an event. How big of an event remains to be seen, but I do have a hard time believing some of the crazier totals some models have shown over the past day and a half (current NAM runs and earlier Euro runs).

It does seem a bit strange that such an intense deformation band could form at this time of year and I also wonder where the moisture is coming from. Jim brought up a good point about the Great Lakes still being fairly warm and I am guessing that is where the majority of the moisture is coming from. If a band does form as depicted by the NAM and earlier Euro runs, obviously everything will be dependent on the track.

My guess at this point is that GFK could see 2-4 inches (and that is on the high side to me... at least at the moment) with northern MN and points north (Lake of the Woods area) getting a pretty hefty dose. I'm so used to systems like this from living in the southeast (temps borderline... changeover characteristics... optimal low path). Didn't think we would have one so hard to forecast up here in the great cold north! Lol.

I have a hard time believing the high amounts as well. Melting if nothing else will diminish the overall amounts. My guess is most likely 3-6" in a narrow corridor, but best case might have a narrow corridor of 6-10".

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A lot of buzz up here about this system. Its interesting to see how the models have evolved over time. About a week ago it seemed like the GFS was the only real model showing a snowy possibility until the NAM ramped up yesterday and at that point the GFS basically looked boring. Now everything seems to be shifting towards a consensus and it seems like there will be an event. How big of an event remains to be seen, but I do have a hard time believing some of the crazier totals some models have shown over the past day and a half (current NAM runs and earlier Euro runs).

It does seem a bit strange that such an intense deformation band could form at this time of year and I also wonder where the moisture is coming from. Jim brought up a good point about the Great Lakes still being fairly warm and I am guessing that is where the majority of the moisture is coming from. If a band does form as depicted by the NAM and earlier Euro runs, obviously everything will be dependent on the track.

My guess at this point is that GFK could see 2-4 inches (and that is on the high side to me... at least at the moment) with northern MN and points north (Lake of the Woods area) getting a pretty hefty dose. I'm so used to systems like this from living in the southeast (temps borderline... changeover characteristics... optimal low path). Didn't think we would have one so hard to forecast up here in the great cold north! Lol.

That is more than reasonable. 2-3" with up to 6"+ across N central and western portions of MN. Cut NAM QPF estimates down by 2/3 and they is closer to reality. Thermals actually look good after the phase with the northern system...and the -5C arctic air pours in behind the cyclone. A lot falls as rain first.

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That is more than reasonable. 2-3" with up to 6"+ across N central and western portions of MN. Cut NAM QPF estimates down by 2/3 and they is closer to reality. Thermals actually look good after the phase with the northern system...and the -5C arctic air pours in behind the cyclone. A lot falls as rain first.

What do you think about the 18z GFS scenario? I think we get a stronger solution (closed off H5 low) but man, both that run and the Euro going gangbusters on the QPF bombs once it really gets cooking.

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What do you think about the 18z GFS scenario? I think we get a stronger solution (closed off H5 low) but man, both that run and the Euro going gangbusters on the QPF bombs once it really gets cooking.

I think both are realistic possibilities, especially across northern MN, and all the models are clearly catching on to a well defined tropopause anomaly...possibly some folding in there. Given the progged baroclinic zone, dry baroclinic dynamics alone would support a closed upper low and well defined frontogenesis band. NAM is keying in on something more substantial...likely moist latent processes feeding back to the synoptic cyclone that I don't foresee occurring given the progged moisture fields. NAM verbatim would have a ripping bent back occlusion with 45-50 kts easily mixing down to the surface in almost a "sting jet" fashion. That would be WSW stuff...possibly blizzard verbatim. Unlikely.

latest 18z GFS dynamic tropopause compared to 06z.

64eb71ae4ef7e2670cdee1bdd0236132.gif

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I think both are realistic possibilities, especially across northern MN, and all the models are clearly catching on to a well defined tropopause anomaly...possibly some folding in there. Given the progged baroclinic zone, dry baroclinic dynamics alone would support a closed upper low and well defined frontogenesis band. NAM is keying in on something more substantial...likely moist latent processes feeding back to the synoptic cyclone that I don't foresee occurring given the progged moisture fields. NAM verbatim would have a ripping bent back occlusion with 45-50 kts easily mixing down to the surface in almost a "sting jet" fashion. That would be WSW stuff...possibly blizzard verbatim. Unlikely.

latest 18z GFS dynamic tropopause compared to 06z.

Yeah it's really easy to see the difference on that. I'm actually excited to see the 0z runs. I've missed forecasting snow!

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My guess looking at 00z NAM progs through 15 hrs is this run will back things up even farther W. GFK in some of these SREF runs flirting with a dryslot, lol. NAm hinting at a legit tropofold and very early cyclogenesis.

It would be my luck to get up here and be the victim of a dry slot! That's all that ever happened to us wherever I was in the southeast. Something tells me later in the Winter I won't be worried too much.

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It would be my luck to get up here and be the victim of a dry slot! That's all that ever happened to us wherever I was in the southeast. Something tells me later in the Winter I won't be worried too much.

The 00z NAM is going ballistic, supporting some of the SREF runs that set up the fronto/defo band clearly in central NODAK.

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This thing's turning into quite the odd system if some of this starts verifying.

Yes, NAM coup if it verifies, and I clearly need to start analyzing more before I open my mouth since. I do think the NAM and WRF runs are catching on to something...I have noticed a huge uptick in the analyzed tropopause anomaly depth/strength over the Canadian Rockies. What still gets me is the extreme rates in the frontal band.

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That is getting dangerously close to blizzard. 925 winds ripping away at 60 kts on backside of deep occlusion west of GFK. That is incredible if the NAM verifies.

was literally just about to mention this looking at the NAM. Turning into a very interesting system.

This is indeed pretty impressive. Look at the low level baroclinic zone. Temps of 14 deg C at 850mb feeding into the circulation.

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i'm compiling some qpf's here per model. and so far from what I can compile, here's what's being spit out grid-point-wise, with some extrapolation between time of snow and time of mix. and interesting numbers from the NAM. the following are liquid QPF's of times when it's snow (no ratios in there) and QPF when the precip is anything other than extrapolated snow (rain, sleet/ice pellets, rain/snow mix, etc) , amounts in inches

  • BIS 0.6 snow / 0.2 other
  • MOT 1.1 snow / 1.2 other
  • GFK 0.6 snow / 0.2 other
  • JMS 1.0 snow / 0.1 other
  • FAR 0.25 snow / 0.1 other
  • DTL 0.15 snow / 0.15 other
  • INL 0.3 snow / 0.2 other
  • DVL 1.7 snow / 0.4 other
  • BJI 0.3 snow / 0.1 other
  • YWG 1.9 snow / 0.5 other
  • YQK 0.4 snow / 0.6 other
  • YHD 0.5 snow / 0.5 other
  • YXL 0.5 snow / 0.6 other
  • YRL 1.5 snow / 0.6 other

we all know this will not be a 10-1 storm, probably more like 8-1 or something like that given the time of year. but just so we have some reference as we compare models and potential impacts, i figured that would help the comparison.

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let's add the 00z GFS numbers now, same format as the previous post.

  • BIS 0.2 snow / 1.0 other
  • MOT 0.3 snow / 0.6 other
  • GFK 0.5 snow / 0.7 other
  • JMS 0.3 snow / 0.5 other
  • FAR 0.4 snow / 0.4 other
  • DTL 0.3 snow / 0.3 other
  • INL 0.5 snow / 1.7 other
  • BJI 0.7 snow / 0.6 other
  • DVL 0.4 snow / 0.6 other
  • YWG 0.4 snow / 0.2 other
  • YQK 1.8 snow / 0.8 other
  • YHD 0.6 snow / 1.7 other
  • YXL 0.4 snow / 1.3 other
  • YRL 0.9 snow / 0.1 other

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canadian regional thru t+48, same format as the other 2 (some areas extend beyond t+48 for this storm, obviously, so take this for what it's worth), but estimated from the graphics as best as i could

  • BIS 0.1 snow / 0.8 other
  • MOT 0.2 snow / 0.6 other
  • GFK 0.4 snow / 1.6 other
  • JMS 0.2 snow / 1.0 other
  • FAR 0.1 snow / 0.6 other
  • DTL 0.3 snow / 1.2 other
  • INL 0.0 snow / 1.6 other
  • DVL 0.5 snow / 0.8 other
  • BJI 0.1 snow / 1.0 other
  • YWG 0.1 snow / 0.6 other
  • YQK 0.2 snow / 1.2 other
  • YHD 0.0 snow / 0.5 other
  • YXL 0.0 snow / 0.2 other
  • YRL 0.2 snow / 0.4 other

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Watching this system with great interest here in Winnipeg. Still trying to wrap my head around a potential early October snowstorm after 15 straight months above normal, but Mother Nature likes to keep things interesting. Note that Canadian GEM model undergoes major upgrade with 12Z run this morning, going down to 10 km resolution (from 15 km) and upgraded 4-d var data assimilation scheme (see link)

http://dd.weatheroffice.ec.gc.ca/bulletins/alphanumeric/20121002/NO/CWAO/17/NOCN03_CWAO_021644___00044

Will be interesting to see how upgrade handles upcoming storm system.

Also, check out spotwx.com for some nice gridpoint meteograms from various models, including ptype and snowfall accums.

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Watching this system with great interest here in Winnipeg. Still trying to wrap my head around a potential early October snowstorm after 15 straight months above normal, but Mother Nature likes to keep things interesting. Note that Canadian GEM model undergoes major upgrade with 12Z run this morning, going down to 10 km resolution (from 15 km) and upgraded 4-d var data assimilation scheme (see link)

http://dd.weatheroff..._021644___00044

Will be interesting to see how upgrade handles upcoming storm system.

Also, check out spotwx.com for some nice gridpoint meteograms from various models, including ptype and snowfall accums.

Here's the new RGEM 10 km resolution from last nights 0Z run...compare the 48hr 15km to the 10km.

15km & 10km

post-252-0-89833700-1349276442_thumb.gif

post-252-0-36012500-1349276483_thumb.gif

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Watching this system with great interest here in Winnipeg. Still trying to wrap my head around a potential early October snowstorm after 15 straight months above normal, but Mother Nature likes to keep things interesting. Note that Canadian GEM model undergoes major upgrade with 12Z run this morning, going down to 10 km resolution (from 15 km) and upgraded 4-d var data assimilation scheme (see link)

http://dd.weatheroff..._021644___00044

Will be interesting to see how upgrade handles upcoming storm system.

Also, check out spotwx.com for some nice gridpoint meteograms from various models, including ptype and snowfall accums.

Here's the new RGEM 10 km resolution from last nights 0Z run...compare the 48hr 15km to the 10km.

15km & 10km

Thanks for the link and images...I did not know it was making this upgrade. No wonder graphics don't work on Ewall.

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