Jason J
@kc5knd.bsky.social
NWS Meteorologist/Master Instructor. Probabilistic forecasting, severe wx, radar, ML/AI, a little bit of this n that!
Cruddy screenshot from my Cloud AWIPS system but in my 30+ years of meteorology experience, the data coming out of #Melissa is nothing short of incredible, and deeply saddening. Jamaica will be in rough shape after this for a long time to come…
October 28, 2025 at 3:15 PM
Cruddy screenshot from my Cloud AWIPS system but in my 30+ years of meteorology experience, the data coming out of #Melissa is nothing short of incredible, and deeply saddening. Jamaica will be in rough shape after this for a long time to come…
Enderlin, ND tor #1 from 20 June 2025 upgraded to EF-5. A good reminder that 1) post-event analyses take time & 2) external expert opinion is invaluable. Having been on EF-5 surveys, seemingly small details can make big difference (i.e. tree damage)
mesonet.agron.iastate.edu/wx/afos/p.ph...
mesonet.agron.iastate.edu/wx/afos/p.ph...
IEM :: PNS from NWS FGF
PNS issued by NWS FGF at 06 Oct 2025 14:30 UTC
mesonet.agron.iastate.edu
October 6, 2025 at 2:50 PM
Enderlin, ND tor #1 from 20 June 2025 upgraded to EF-5. A good reminder that 1) post-event analyses take time & 2) external expert opinion is invaluable. Having been on EF-5 surveys, seemingly small details can make big difference (i.e. tree damage)
mesonet.agron.iastate.edu/wx/afos/p.ph...
mesonet.agron.iastate.edu/wx/afos/p.ph...
Winter is coming (but taking a hiatus for the next week according to the ensembles). Snow on the Front Range peaks, but not on the Flatirons. #cowx #snowseason (full disclosure; Apple AI helped remove cars on US 36; stop & go traffic on Davidson Mesa brought you this pic)
September 24, 2025 at 1:40 PM
Winter is coming (but taking a hiatus for the next week according to the ensembles). Snow on the Front Range peaks, but not on the Flatirons. #cowx #snowseason (full disclosure; Apple AI helped remove cars on US 36; stop & go traffic on Davidson Mesa brought you this pic)
Folks around McCook, Nebraska are going to have a free ice cold swimming pool; storm and occasional supercell parked just north of the surface frontal boundary dropping 3” hail and radar estimates pushing 4” of rain… #newx
September 16, 2025 at 9:34 PM
Folks around McCook, Nebraska are going to have a free ice cold swimming pool; storm and occasional supercell parked just north of the surface frontal boundary dropping 3” hail and radar estimates pushing 4” of rain… #newx
It’s hard to see but that is an Extreme Forecast Index of 0.5 off the coast of SoCal late week. The black lines are Shift of Tails…of over 8 (contour maxes out at 8). NWS EFI/SoT (firewalled) shows greater than 10 SoT! 😳 Chance for extreme precip is medium but could be extreme w/ high SoT values!
September 15, 2025 at 2:18 PM
It’s hard to see but that is an Extreme Forecast Index of 0.5 off the coast of SoCal late week. The black lines are Shift of Tails…of over 8 (contour maxes out at 8). NWS EFI/SoT (firewalled) shows greater than 10 SoT! 😳 Chance for extreme precip is medium but could be extreme w/ high SoT values!
Interesting sky this morning heading into work. We’re almost to the right time of year when I’ll be heading out when there will be more colors (you know, to avoid the morning CU BOU student rush hour to get there just in time for their first class). #cowx
September 10, 2025 at 1:40 PM
Interesting sky this morning heading into work. We’re almost to the right time of year when I’ll be heading out when there will be more colors (you know, to avoid the morning CU BOU student rush hour to get there just in time for their first class). #cowx
Great morning to make the bike ride on Big Dry Creek trail from City Park to Standley Lake. Some spots felt in the 40s along creek drainage which was great until I climbed out the last 1.5 miles up to the lake. That was a bit warm in full sun & out of the cold air drainage. 12.72 mi round trip
September 1, 2025 at 4:56 PM
Great morning to make the bike ride on Big Dry Creek trail from City Park to Standley Lake. Some spots felt in the 40s along creek drainage which was great until I climbed out the last 1.5 miles up to the lake. That was a bit warm in full sun & out of the cold air drainage. 12.72 mi round trip
Xcel Energy is changing TOU rate structure in October. Gone is Mid-Peak 1-3pm and Peak moves from 3-7pm to 5-9pm. So as a good data scientist does, spent the last 2 hours in Python with my 2024 hourly net metering data & found out that my change in cost would have been...$2.18. For the year.
August 23, 2025 at 5:04 PM
Xcel Energy is changing TOU rate structure in October. Gone is Mid-Peak 1-3pm and Peak moves from 3-7pm to 5-9pm. So as a good data scientist does, spent the last 2 hours in Python with my 2024 hourly net metering data & found out that my change in cost would have been...$2.18. For the year.
Yeah, it’s the 95th Percentile from NBM V5.0 and 10 days out…but it is still a chance for snow! #winteriscoming #wishcasting
August 22, 2025 at 3:01 PM
Yeah, it’s the 95th Percentile from NBM V5.0 and 10 days out…but it is still a chance for snow! #winteriscoming #wishcasting
Reposted by Jason J
Numerical weather prediction models (ECMWF IFS) still outperform AI weather models in forecasting record-breaking hot and cold extremes and unseen wind extremes
Preprint
arxiv.org/abs/2508.15724
with Zhongwei Zhang @erichfischer.bsky.social @zscheischlerjak.bsky.social and Sebastian Engelke
Preprint
arxiv.org/abs/2508.15724
with Zhongwei Zhang @erichfischer.bsky.social @zscheischlerjak.bsky.social and Sebastian Engelke
Numerical models outperform AI weather forecasts of record-breaking extremes
Artificial intelligence (AI)-based models are revolutionizing weather forecasting and have surpassed leading numerical weather prediction systems on various benchmark tasks. However, their ability to ...
arxiv.org
August 22, 2025 at 5:43 AM
Numerical weather prediction models (ECMWF IFS) still outperform AI weather models in forecasting record-breaking hot and cold extremes and unseen wind extremes
Preprint
arxiv.org/abs/2508.15724
with Zhongwei Zhang @erichfischer.bsky.social @zscheischlerjak.bsky.social and Sebastian Engelke
Preprint
arxiv.org/abs/2508.15724
with Zhongwei Zhang @erichfischer.bsky.social @zscheischlerjak.bsky.social and Sebastian Engelke
The HRRR smoke forecasts were bad on the 00Z and 12Z runs; smoke settled into Vail Valley so we “cheated” and drove up to the Shrine Pass lot. Made it up to 11.9 kft today and it was worth it; smoke was not bad above the inversion, it was cool, & the last of the wildflowers were in bloom. #colorado
August 9, 2025 at 10:06 PM
The HRRR smoke forecasts were bad on the 00Z and 12Z runs; smoke settled into Vail Valley so we “cheated” and drove up to the Shrine Pass lot. Made it up to 11.9 kft today and it was worth it; smoke was not bad above the inversion, it was cool, & the last of the wildflowers were in bloom. #colorado
So many takes (good & bad) on the TX Hill Country flooding. Having spent a large part of my life in the heart of Hill Country, difference of 5 miles or less can mean soaking rain or flash flood. Look at hydromet.lcra.org precip & stream flow; you can see what I mean (basins are shaded in these maps)
July 13, 2025 at 3:47 PM
So many takes (good & bad) on the TX Hill Country flooding. Having spent a large part of my life in the heart of Hill Country, difference of 5 miles or less can mean soaking rain or flash flood. Look at hydromet.lcra.org precip & stream flow; you can see what I mean (basins are shaded in these maps)
Reposted by Jason J
"Questioning is the way of learning,"
Encourage your children to ask questions, not to accept existing answers.
Encourage your children to ask questions, not to accept existing answers.
July 13, 2025 at 2:20 PM
"Questioning is the way of learning,"
Encourage your children to ask questions, not to accept existing answers.
Encourage your children to ask questions, not to accept existing answers.
A 300x timelapse from my neighbor; “You study clouds, what is this stuff before sunrise? We saw it when we went to let (dog’s name) out…”
Sure looks like noctilucent clouds to me! #cowx #noctilucent
Sure looks like noctilucent clouds to me! #cowx #noctilucent
July 11, 2025 at 12:16 PM
A 300x timelapse from my neighbor; “You study clouds, what is this stuff before sunrise? We saw it when we went to let (dog’s name) out…”
Sure looks like noctilucent clouds to me! #cowx #noctilucent
Sure looks like noctilucent clouds to me! #cowx #noctilucent
Another good case for why Composite Reflectivity is useful out here up against the Front Range. Could hear grit hitting windows & rattling in the frame as microburst from ample virga is taking place. Mesa Lab showing gusts to 30 mph but wouldn’t be surprised if higher gusts possible in other areas.
July 8, 2025 at 8:57 PM
Another good case for why Composite Reflectivity is useful out here up against the Front Range. Could hear grit hitting windows & rattling in the frame as microburst from ample virga is taking place. Mesa Lab showing gusts to 30 mph but wouldn’t be surprised if higher gusts possible in other areas.
Once again, right conditions come together to result in catastrophic flash flooding across portions of the wrn Texas Hill Country. I'm 6th gen from down there; the "old timers" would talk about floods that would come out of nowhere uprooting trees along normally dry banks. This is no exception...
July 4, 2025 at 7:50 PM
Once again, right conditions come together to result in catastrophic flash flooding across portions of the wrn Texas Hill Country. I'm 6th gen from down there; the "old timers" would talk about floods that would come out of nowhere uprooting trees along normally dry banks. This is no exception...
Been busy with some things & slacking on food posts from #Vietnam. Today was the best donuts I’ve had here, always delightful Bạc Xỉu coffee, and Bún Chả - bacon, pork patties in a sweet fish sauce with rice noodles and veggies. So stuffed!!
June 17, 2025 at 2:57 PM
Been busy with some things & slacking on food posts from #Vietnam. Today was the best donuts I’ve had here, always delightful Bạc Xỉu coffee, and Bún Chả - bacon, pork patties in a sweet fish sauce with rice noodles and veggies. So stuffed!!
This is how some restaurants make the best phở in Vietnam; broth that has been simmering for months and in one place supposedly years. I'm still around after first having it in 2019 with no ill effects...and it was delicious.
Perpetual stew is a soup that stews for days, weeks or even years on end. It's having a moment on social media. But is it safe?
Want to try perpetual stew? Some tips for avoiding foodborne illness
Perpetual stew is a soup that stews for days, weeks or even years on end. It's having a moment on social media. But is it safe?
n.pr
June 12, 2025 at 5:53 PM
This is how some restaurants make the best phở in Vietnam; broth that has been simmering for months and in one place supposedly years. I'm still around after first having it in 2019 with no ill effects...and it was delicious.
First intense downpour (luckily while under cover) in #Vietnam where it’s 55-60 dBZ. Second pic you can just make outline of a building 2 blocks away. Been dumping for 15 minutes & just now heard 1st rumble of thunder. Meteorology in SE Asia is so fascinating, wish I had a rain gage here!
June 10, 2025 at 10:10 AM
First intense downpour (luckily while under cover) in #Vietnam where it’s 55-60 dBZ. Second pic you can just make outline of a building 2 blocks away. Been dumping for 15 minutes & just now heard 1st rumble of thunder. Meteorology in SE Asia is so fascinating, wish I had a rain gage here!
You know dinner in #Vietnam will be amazing when you turn down a side alley in old town Hoi An and your knees are higher than the table when you sit down in your chair. Lan Thai; yes, we had Thai to see if it was worthy of the 4.9 ⭐️ rating.
It is!
It is!
June 8, 2025 at 11:56 AM
You know dinner in #Vietnam will be amazing when you turn down a side alley in old town Hoi An and your knees are higher than the table when you sit down in your chair. Lan Thai; yes, we had Thai to see if it was worthy of the 4.9 ⭐️ rating.
It is!
It is!