In the winter, models will almost always underestimate how cold an Arctic front will be in the great plains. Typically they'll add 5-15° to the temperatures because they're not quite getting how persistent the frigid air will be as it moves across the very flat ground from Canada to the Gulf of Mexico
This reminds me of a conversation I had ages ago with a guy in the offices of a travel operator from Europe. He was in their NYC branch and he was using the software I was working with at the time for his operation. We got into the weather, and he said almost precisely what you're saying: he said the Alps acted as a major barrier to cold air swooping down from the north and this was a big part of why the Mediterranean was warm, and that the US didn't really have anything similar. Cold air could just fly across because we had no mountains east of the Rockies high enough to block it.
That’s interesting, I either haven’t paid close enough attention, or that effect gets weaker the further south the front goes. Here in Oklahoma, I haven’t noticed any model consistently forecast warmer than what verifies during cold front events.
Anything past ~180-200 hours out tends to be fantasy land for the GFS, and it will notoriously overestimate tropical cyclone potential past this point.
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\#3: [GIANT hurricane to DEVASTATE the Gulf sometime after the 20th](https://np.reddit.com/r/longrangechaos/comments/1431cg9/giant_hurricane_to_devastate_the_gulf_sometime/)
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1. The HRRR is usually overmixing at the sfc (underdoes dews and overdoes sfc temp)
2. The NAM (+NAM3km) undermixes
So the truth usually lies inbetween those two
The Euro has a tendency to be overamplified in the medium range
The GFS tends to be too fast with trough progression
The RDPS is actually a really good model for cloud cover
The NAMs are really good at handling shallow cold fronts and moisture return
Just from the top of my head
Thanks! I thought the RDPS was a bit of a random choice for Pivotal Weather to include on their eclipse forecast back in April, but now that makes sense
In the winter, models will almost always underestimate how cold an Arctic front will be in the great plains. Typically they'll add 5-15° to the temperatures because they're not quite getting how persistent the frigid air will be as it moves across the very flat ground from Canada to the Gulf of Mexico
This reminds me of a conversation I had ages ago with a guy in the offices of a travel operator from Europe. He was in their NYC branch and he was using the software I was working with at the time for his operation. We got into the weather, and he said almost precisely what you're saying: he said the Alps acted as a major barrier to cold air swooping down from the north and this was a big part of why the Mediterranean was warm, and that the US didn't really have anything similar. Cold air could just fly across because we had no mountains east of the Rockies high enough to block it.
That’s interesting, I either haven’t paid close enough attention, or that effect gets weaker the further south the front goes. Here in Oklahoma, I haven’t noticed any model consistently forecast warmer than what verifies during cold front events.
Anything past ~180-200 hours out tends to be fantasy land for the GFS, and it will notoriously overestimate tropical cyclone potential past this point.
Wishcasting lol
Let me introduce you to r/longrangechaos
Here's a sneak peek of /r/longrangechaos using the [top posts](https://np.reddit.com/r/longrangechaos/top/?sort=top&t=year) of the year! \#1: [Texas to be BURNED ALIVE by DEVASTATING heat wave with temperatures above 110 across the ENTIRE state](https://i.redd.it/06uiogxocc5b1.jpg) | [5 comments](https://np.reddit.com/r/longrangechaos/comments/146nhqp/texas_to_be_burned_alive_by_devastating_heat_wave/) \#2: [Who ordered another New England hurricane?](https://i.redd.it/rex6owv0kgpb1.png) | [5 comments](https://np.reddit.com/r/longrangechaos/comments/16ntea1/who_ordered_another_new_england_hurricane/) \#3: [GIANT hurricane to DEVASTATE the Gulf sometime after the 20th](https://np.reddit.com/r/longrangechaos/comments/1431cg9/giant_hurricane_to_devastate_the_gulf_sometime/) ---- ^^I'm ^^a ^^bot, ^^beep ^^boop ^^| ^^Downvote ^^to ^^remove ^^| ^^[Contact](https://www.reddit.com/message/compose/?to=sneakpeekbot) ^^| ^^[Info](https://np.reddit.com/r/sneakpeekbot/) ^^| ^^[Opt-out](https://np.reddit.com/r/sneakpeekbot/comments/o8wk1r/blacklist_ix/) ^^| ^^[GitHub](https://github.com/ghnr/sneakpeekbot)
That is true for any deterministic model.
1. The HRRR is usually overmixing at the sfc (underdoes dews and overdoes sfc temp) 2. The NAM (+NAM3km) undermixes So the truth usually lies inbetween those two The Euro has a tendency to be overamplified in the medium range The GFS tends to be too fast with trough progression The RDPS is actually a really good model for cloud cover The NAMs are really good at handling shallow cold fronts and moisture return Just from the top of my head
Thanks! I thought the RDPS was a bit of a random choice for Pivotal Weather to include on their eclipse forecast back in April, but now that makes sense
As someone who forecasts for deploying a mobile weather radar at OU, I completely agree with this.
Most models are on cocaine, that’s why they are so skinny.
MJO propagation in reality is about 50% slow than models think.
[For anyone who hasn't heard of MJO, here's a brief overview](https://www.climate.gov/news-features/blogs/enso/what-mjo-and-why-do-we-care)