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Simon Lee @simonleewx.com · 8h

Aye I only spotted it last night when I revisited the chart for Floris!

Simon Lee @simonleewx.com · 17h

Storm Floris at 12 UTC 4 August 2025 vs. Storm Amy at 18 UTC 3 October 2025.

Strikingly similar synoptic patterns and locations of the two storms separated by only two months!

Storm Floris surface pressure and fronts from the Met Office

Storm Amy surface pressure and fronts from the Met Office

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Simon Lee @simonleewx.com · 19h

Excellent! Glad to hear it's still going.

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Simon Lee @simonleewx.com · 22h

Ah, I loved that view during my time at UoR! Hope you are enjoying your time there.

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Simon Lee @simonleewx.com · 1d

Reminded me of this rmets.onlinelibrary.wiley.com/doi/10.1002/...

The gust that never was: a meteorological instrumentation mystery

Time series of 10-m wind speeds (maximum gust and minimum lull, units ms−1) at the University of Reading Atmospheric Observatory (51.441°N, 0.938°W, altitude 66m above MSL) for each minute 0000–2359 ...

rmets.onlinelibrary.wiley.com

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Reposted by Simon Lee

Zeke Hausfather @hausfath.bsky.social · 1d

And here is the percentage of the world's land area setting a new all-time monthly maximum temperature record in each decade:

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Simon Lee @simonleewx.com · 2d

The west–east temperature contrast across North America is a hallmark of the Pacific Ridge regime, which is currently at 1.5–2 standard deviations simonleewx.com/ecmwf_north_...

Weather Regime Index plots from the ECMWF IFS subseasonal ensemble

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Simon Lee @simonleewx.com · 3d

Amy is a separate low pressure system, hence the new name. It did spawn from Humberto but the closed low is considered different.

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Simon Lee @simonleewx.com · 3d

Wonder what NH mean alone will look like?

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Simon Lee @simonleewx.com · 3d

This is absolutely staggering.

Zack Labe @zacklabe.com · 4d

Record warm ocean temperatures continued in September across the North Pacific Ocean, with a number of consequential impacts (including on downstream weather patterns).

This graph shows the average for a band across the midlatitudes for every September from 1854-2025 using @noaa.gov ERSSTv5 data.

Green line graph time series of average sea surface temperature anomalies for each September from 1850 through 2025 for only the midlatitude region of the North Pacific Ocean. There is large interannual variability, but an overall long-term increasing trend. Anomalies are computed relative to a 1981-2010 baseline. 2025 is a record high.

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Simon Lee @simonleewx.com · 3d

Beaufort Force 12 (73mph or greater) is “hurricane force”, and that is referred to in storms in the UK where appropriate. But there is a VERY big difference between hurricane force winds and an actual hurricane.

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Simon Lee @simonleewx.com · 3d

Please provide evidence to support your claims.

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Simon Lee @simonleewx.com · 3d

“Hurricanes” are tropical cyclones, which feed off the energy of high oceanic heat. They are an entirely different type of storm which do not reach our shores. The storms we experience, like Amy, feed off the temperature contrast between cold and warm air masses.

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Reposted by Simon Lee

Eddy Graham ("eddy weather") @eddywx.bsky.social · 3d

#StormAmy boomerang loop of #Meteosat12 #MTG water vapour 6.2micron channel imagery over 36h (3-4 Oct 2025) shows extent & expansion of deep dry air intrusion, before being spun majestically around the record-breaking deep cyclone centre #VorticityInAction

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Simon Lee @simonleewx.com · 3d

Yes, Amy spawned off Humberto at the end of its life — in fact, for a while, it looked like the storm hitting the UK would be ex-Humberto until it became clearer that it was a separate circulation.

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Simon Lee @simonleewx.com · 3d

More reason not to trust AI for such things

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Simon Lee @simonleewx.com · 3d

Perhaps a tabloid newspaper “named” it then. Whatever happened, it was not official.

Simon Lee @simonleewx.com · 4d

Evolution of #StormAmy from 18 UTC 1 October through 12 UTC 4 October per Met Office analyses. The initial disturbance was perfectly phased with a wave in the jet, undergoing explosive cyclogenesis & evolving into a powerful Shapiro–Keyser cyclone, setting low pressure records for the time of year.

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Reposted by Simon Lee

Netweather @netweather.tv · 4d

Storm Amy has brought severe disruption to Scotland with 96mph winds and widespread power outages, while setting a new October pressure record for the British Isles at 947.9hPa on Friday.

Storm Amy sets new October pressure record but settled conditions return next week

Storm Amy has brought severe disruption to Scotland with 96mph winds and widespread power outages, while setting a new October pressure record for the British Isles at 947.9hPa on Friday.<br/>

www.netweather.tv

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Simon Lee @simonleewx.com · 4d

When? We have not had a Storm Amy already in western Europe this year.

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Simon Lee @simonleewx.com · 4d

Perhaps there was some latency with appreciating this was turning into the higher end scenario. They did use the word “expected” rather than “forecast”

Simon Lee @simonleewx.com · 4d

I’m a bit perplexed why Network Rail Scotland are claiming Storm Amy to have hit “much harder and more quickly than expected” — forecasts from earlier today seem correct to me; intensity shifted up from yesterday’s forecasts, conveyed in warning text mentioning gusts up to 100mph (as observed)

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Simon Lee @simonleewx.com · 4d

Lights flickering a bit in Guardbridge

Simon Lee @simonleewx.com · 4d

40 hPa drop in Amy’s central pressure since 18Z yesterday

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Simon Lee @simonleewx.com · 4d

#StormAmy down to 952 hPa over Outer Hebrides on 18Z analysis from the Met Office, which continues the Shapiro-Keyser structure from the 12Z analysis (frontal fracture)

Surface pressure and frontal analysis from the Met Office

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