Summer's done and the weather turned. Hurricane Lowell hit Hawaii, TSMC's fabs sat under heat then flood warnings, and Generac is up 10% since Labor Day.

New York went from an 82°F high on 17 September to a 58°F low the night before, per the Central Park station on the tape. Major Hurricane Lowell hit Hawaii on 5 September. The tape's hazard layer, which reads NOAA alerts over the sites that matter, put TSMC's fab sites under Extreme Heat Warnings on 9 and 10 September and under Flash Flood and Flood Warnings on 16 and 17 September; Intel, Marathon, Chevron and PBF sites sat under the same heat warnings. Generac, the generator maker, is up 10.7% since Labor Day; Home Depot is down 6.6%; Allstate down 3.8%.

in plain EnglishWeather moves markets more than people think. When a hurricane or a heatwave hits, insurers pay out, generator makers sell more, and factories slow down. Chip fabs are the most sensitive of all: they need steady power and water and no floods, so the tape watches the weather alerts over every big fab and refinery. This month TSMC's sites in Taiwan sat under extreme heat warnings and then flood warnings within a week. Dave tells it from a sushi bar on the Lower East Side, because the city is back from summer and so is he.

Reported Sunday 20 September 2026 · every number dated to its source, latest 18 September 2026

1 · evidence every number, with its source and its date

Central Park low 58°F on 16 Sept · high 82°F on 17 Sept · 0.96 in of rain on 13 Sept

New York, the turn

daily weather, Central Park station (Kalshi settlement) on the AirPort tape · 2026-09-17

"Verizon waives charges for Hurricane Lowell, prepares network in Hawai'i" as the major hurricane approached

Hurricane Lowell

news on the tape, 5 Sept · 2026-09-05

Extreme Heat Warning · operations-threat · 9 and 10 Sept

TSMC fab sites · heat

hazard layer on the AirPort tape (NOAA alerts over fab sites) · 2026-09-10

Flash Flood Warning 16 Sept · Flood Warning 17 Sept · operations-threat

TSMC fab sites · flood

hazard layer on the AirPort tape · 2026-09-17

Intel fabs · Marathon, Chevron and PBF refineries · 9–10 Sept

Also under the heat warnings

hazard layer on the AirPort tape · 2026-09-10

an Exxon site under a Hurricane Watch, severity Severe

Hurricane watch, 1 Sept

hazard layer on the AirPort tape · 2026-09-01

$207.55 · +10.7% since Labor Day · +47% this year

Generac (GNRC)

regular-session closes · the AirPort tape · 2026-09-18

−6.6% · −3.8% · +1.4% since Labor Day

Home Depot (HD) · Allstate (ALL) · Travelers (TRV)

regular-session closes · the AirPort tape · 2026-09-18

+1.4% · +2.5% since Labor Day · +36% · +70% this year

TSMC (TSM) · semis (SOXX)

regular-session closes · the AirPort tape · 2026-09-18

"3 P&C insurers to add for better returns in sluggish September": severe weather, wildfires, rising costs

Insurers

news on the tape (Zacks), 3 Sept · 2026-09-03

Generac (GNRC)+47.1% since 2026-01-02

open $141 2026-01-02now $208 2026-09-18from the high -29.8%179 trading days · regular-session closes from the AirPort tape

TSMC (TSM)+35.9% since 2026-01-02

open $320 2026-01-02now $435 2026-09-18from the high -8.9%179 trading days · regular-session closes from the AirPort tape

Home Depot (HD)-13.3% since 2026-01-02

open $346 2026-01-02now $300 2026-09-18from the high -23.3%179 trading days · regular-session closes from the AirPort tape

2 · relations who this touches

TSMC (TSM)Generac (GNRC)New York weather Taiwan

3 · history · 4 · analogues · 5 · ask Pro

AirPort has been watching this since before it was news. The trail, the last times this shape happened, and Ask, scoped to this story.GO DEEPER

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