Trader consensus on the Polymarket distribution, with the highest implied probability on below-normal totals under 275 mm, reflects the Hong Kong Observatory’s September 2026 outlook for normal-to-below-normal rainfall amid a rapidly strengthening, potentially record El Niño. Equatorial Pacific sea-surface temperatures have risen sharply, with models projecting a very strong event peaking in November–December that typically suppresses South China Sea convection and favors high-pressure ridging over the region during the second half of the month. Early-September tropical cyclone activity, including systems crossing the northern South China Sea, introduces short-term rainfall potential, yet climatological analogs and dynamical guidance indicate reduced overall moisture transport. Key variables include the precise timing and intensity of El Niño teleconnections, the frequency and tracks of late-season tropical cyclones, and any deviations in the strengthening subtropical anticyclone. Forecast updates from the Observatory and major centers will refine these probabilities as the month progresses.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedPrecipitation in Hong Kong in September?
Precipitation in Hong Kong in September?
<275mm 31%
275-300mm 15%
450-500mm 11%
400-450mm 10%
NEW
NEW
Sep 30, 2026
<275mm
31%
275-300mm
15%
300-325mm
7%
325-350mm
9%
350-375mm
7%
375-400mm
7%
400-450mm
8%
450-500mm
11%
500-550mm
8%
550mm+
5%
<275mm 31%
275-300mm 15%
450-500mm 11%
400-450mm 10%
NEW
NEW
Sep 30, 2026
<275mm
$856 Vol.
31%
275-300mm
$128 Vol.
15%
300-325mm
$128 Vol.
7%
325-350mm
$128 Vol.
9%
350-375mm
$125 Vol.
7%
375-400mm
$125 Vol.
7%
400-450mm
$150 Vol.
8%
450-500mm
$125 Vol.
11%
500-550mm
$128 Vol.
8%
550mm+
$150 Vol.
5%
This market will resolve according to the total precipitation in mm in Hong Kong between September 1 and September 30, 2026, according to the Hong Kong Observatory.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Trader consensus on the Polymarket distribution, with the highest implied probability on below-normal totals under 275 mm, reflects the Hong Kong Observatory’s September 2026 outlook for normal-to-below-normal rainfall amid a rapidly strengthening, potentially record El Niño. Equatorial Pacific sea-surface temperatures have risen sharply, with models projecting a very strong event peaking in November–December that typically suppresses South China Sea convection and favors high-pressure ridging over the region during the second half of the month. Early-September tropical cyclone activity, including systems crossing the northern South China Sea, introduces short-term rainfall potential, yet climatological analogs and dynamical guidance indicate reduced overall moisture transport. Key variables include the precise timing and intensity of El Niño teleconnections, the frequency and tracks of late-season tropical cyclones, and any deviations in the strengthening subtropical anticyclone. Forecast updates from the Observatory and major centers will refine these probabilities as the month progresses.
This market will resolve according to the total precipitation in mm in Hong Kong between September 1 and September 30, 2026, according to the Hong Kong Observatory.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: Aug 31, 2026, 9:41 AM ET
Volume
$2,041End Date
Oct 1, 2026Market Opened
Aug 31, 2026, 9:41 AM ETResolver
0x69c47De9D...This market will resolve according to the total precipitation in mm in Hong Kong between September 1 and September 30, 2026, according to the Hong Kong Observatory.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.Trader consensus on the Polymarket distribution, with the highest implied probability on below-normal totals under 275 mm, reflects the Hong Kong Observatory’s September 2026 outlook for normal-to-below-normal rainfall amid a rapidly strengthening, potentially record El Niño. Equatorial Pacific sea-surface temperatures have risen sharply, with models projecting a very strong event peaking in November–December that typically suppresses South China Sea convection and favors high-pressure ridging over the region during the second half of the month. Early-September tropical cyclone activity, including systems crossing the northern South China Sea, introduces short-term rainfall potential, yet climatological analogs and dynamical guidance indicate reduced overall moisture transport. Key variables include the precise timing and intensity of El Niño teleconnections, the frequency and tracks of late-season tropical cyclones, and any deviations in the strengthening subtropical anticyclone. Forecast updates from the Observatory and major centers will refine these probabilities as the month progresses.
This market will resolve according to the total precipitation in mm in Hong Kong between September 1 and September 30, 2026, according to the Hong Kong Observatory.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
If the reported data falls exactly between two brackets, this market will resolve to the higher bracket.
The resolution source for this market will be the Hong Kong Observatory, specifically the "Total Rainfall (mm)" figure for all days in September 2026 under the "Daily Extract" at the https://www.weather.gov.hk/en/cis/climat.htm link once figures are finalized for the specified range.
If the relevant data is not available by December 7, 2026, 11:59 PM ET, another credible resolution source will be chosen.
The resolution source for this market measures precipitation to 1 decimal place (e.g., 1.5), thus, this is the level of precision that will be used when resolving this market. Any revisions to precipitation recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Volume
$2,041End Date
Oct 1, 2026Market Opened
Aug 31, 2026, 9:41 AM ETResolver
0x69c47De9D...Trader consensus on the Polymarket distribution, with the highest implied probability on below-normal totals under 275 mm, reflects the Hong Kong Observatory’s September 2026 outlook for normal-to-below-normal rainfall amid a rapidly strengthening, potentially record El Niño. Equatorial Pacific sea-surface temperatures have risen sharply, with models projecting a very strong event peaking in November–December that typically suppresses South China Sea convection and favors high-pressure ridging over the region during the second half of the month. Early-September tropical cyclone activity, including systems crossing the northern South China Sea, introduces short-term rainfall potential, yet climatological analogs and dynamical guidance indicate reduced overall moisture transport. Key variables include the precise timing and intensity of El Niño teleconnections, the frequency and tracks of late-season tropical cyclones, and any deviations in the strengthening subtropical anticyclone. Forecast updates from the Observatory and major centers will refine these probabilities as the month progresses.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
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