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Jason J @kc5knd.bsky.social · 2d

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...

IEM :: PNS from NWS FGF

PNS issued by NWS FGF at 06 Oct 2025 14:30 UTC

mesonet.agron.iastate.edu

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Jason J @kc5knd.bsky.social · 14d

This analysis ( events.ecmwf.int/event/333/co... ) from ECMWF indicates it isn’t as much as many mets think. Losing satellite data has greater impact than losing radiosondes (labeled TEMP in the image) on their modeling systems. Can’t find a similar study for NWS models, at least not from home…

ECMWF study showing that radiosondes aren’t even in the top 10 for improving their model forecasts.

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Jason J @kc5knd.bsky.social · 14d

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)

Snow on the peaks of the Front Range but not on the Flatirons. Sure sign winter is coming

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Jason J @kc5knd.bsky.social · 15d

Colorado has entered the chat…

Snow falling at the Eisenhower Johnson Memorial tunnel on 9/23

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Jason J @kc5knd.bsky.social · 21d

First dusting of snow on the Front Range? Or hail from the storms last night? Either way, winter is coming and I’m ready for it! #cowx

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Jason J @kc5knd.bsky.social · 22d

Eh I'll still approve 🧐

Also will inifinity% agree with D. Some of the best food we've ever had travelling in Vietnam, Taiwan, and Jordan. Can't tell if Istanbul falls in D but that too. Stinks that the focus falls in the Mediterranean because if Greece falls into D...man. Best zone of them all.

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Jason J @kc5knd.bsky.social · 22d

If G includes NYC, and KC for BBQ; then your choices are approved.

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Jason J @kc5knd.bsky.social · 22d

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

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Jason J @kc5knd.bsky.social · 23d

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!

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Jason J @kc5knd.bsky.social · 28d

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

Interesting clouds over the Flatirons this morning

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Jason J @kc5knd.bsky.social · Sep 1

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

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Jason J @kc5knd.bsky.social · Aug 25

But, en.wikipedia.org/wiki/NEXRAD does have all the “start dates” for data which quick spot checks and cross referencing with NCEI inventory shows matches. Roughly can guess installs started 2-4 months before these dates.

NEXRAD - Wikipedia

en.wikipedia.org

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Jason J @kc5knd.bsky.social · Aug 25

No luck on my files/documents; the one I was thinking of may have gotten lost in our move to DSRC or shuffling between office and our storage. Bummed because it had a graphic of 88D install and operational dates.

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Jason J @kc5knd.bsky.social · Aug 23

Lots of variables I didn't account for; solar system production being biggest. Looked at flat rate option, that would have cost $15.62 more. Didn't take into account fees, fuel surcharges, etc, just raw power cost for time of use.

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Jason J @kc5knd.bsky.social · Aug 23

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.

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Jason J @kc5knd.bsky.social · Aug 22

Post-frontal airmass pushing up against the Flatirons and 68°. So nice… #cowx

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Jason J @kc5knd.bsky.social · Aug 22

Yeah, it’s the 95th Percentile from NBM V5.0 and 10 days out…but it is still a chance for snow! #winteriscoming #wishcasting

NBM V5 starting to show snow in the 95th percentile so it is saying, yes, there is a chance!

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Reposted by Jason J

Erich Fischer @erichfischer.bsky.social · Aug 22

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

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

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Jason J @kc5knd.bsky.social · Aug 21

What kind of reference are you looking for; I have some old docs from back during pre-MAR & MAR that may help…

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Jason J @kc5knd.bsky.social · Aug 18

One of the pivotal events that led me to become a meteorologist. Visiting grandparents in Katy when it hit. Remember checking the aneroid barometer on the wall and watching it fall. Grandfather was in the VFD so we went out after the eyewall passed by to check for damage.

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Jason J @kc5knd.bsky.social · Aug 18

Or it could be the case of “why is there this constant source in the COLMA north of my house? Oh wait, that’s a dead pixel on my monitor showing up purple because it’s still there when I change tabs to GOES visible. In greyscale. Except for that one pixel”. After 20 minutes of head scratching. 🤦🏻‍♂️

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Jason J @kc5knd.bsky.social · Aug 10

We had occasional very light ash fall (fine, light gray particulates) in Vail starting around 7pm guessing from this fire based on the HRRR smoke field. Crazy that it is lofting material that far away!

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Jason J @kc5knd.bsky.social · Aug 9

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

Panoramic view from the Shrine Pass Road trail looking east northeast

Fireweed (Chamaenerion angustifolium) on full display

Looking south from Shrine Pass Road trial

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Jason J @kc5knd.bsky.social · Aug 8

Much needed nature therapy today. Gore Creek Trail… #colorado

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Jason J @kc5knd.bsky.social · Aug 2

Once again, my #ADSB station showing why it's risk flying into DEN on a summer afternoon. Ground stop for departing flights, multiple racetrack hold patterns, & several diverts likely due to fuel or unable to wait to get into DEN. #avgeek #cowx

Automatic Direct Surveillance Broadcast (ADSB) image showing multiple hold areas for flights into Denver International as well as some flights diverting to alternate airports now

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