Historical analogue confidence

JADE ANALYSIS

The question is not which year looks similar. It is how much confidence the historical outcome deserves as an analogue for today.

Current state · 2026

oni
-0.54 z -0.58
soi
+1.33 z +0.78
iod
-0.40 z -0.57
antecedent_mm
+3070.80 z +4.08
Outcome
1,566.6 mm

Analogue usefulness

0.3501

1 − (stdev of closest-8 outcomes / climatological stdev). Positive values mean analogues tighten the outcome distribution. Not a probability.

Closest-8 outcome range 607.31,491.2 mm · climatology σ 505.7 mm

Not in the state vector

  • · MJO
  • · IPO/PDO
  • · SST fields
  • · atmospheric moisture
  • · soil moisture
  • · synoptic regime

Closest historical states

YearDistanceOutcomeMatchesDiffers
20012.1778916 mmoni, soi, iodantecedent_mm
19752.2802681.6 mmoni, soi, iodantecedent_mm
19993.0026932.8 mmsoi, iodantecedent_mm
19543.09971,307 mmiodantecedent_mm
19613.2232607.3 mmoni, soiantecedent_mm
20123.22761,286.2 mmoni, soiiod, antecedent_mm
20103.47751,491.2 mmoni, soi, antecedent_mm
19563.53321,331 mmsoi, iodantecedent_mm
  • 2001: matched oni, soi, iod; differed antecedent_mm; wet-season outcome 916.0 mm.
  • 1975: matched oni, soi, iod; differed antecedent_mm; wet-season outcome 681.6 mm.
  • 1999: matched soi, iod; differed antecedent_mm; wet-season outcome 932.8 mm.
  • 1954: matched iod; differed antecedent_mm; wet-season outcome 1307.0 mm.
  • 1961: matched oni, soi; differed antecedent_mm; wet-season outcome 607.3 mm.
  • 2012: matched oni, soi; differed iod, antecedent_mm; wet-season outcome 1286.2 mm.
  • 2010: matched nothing closely; differed oni, soi, antecedent_mm; wet-season outcome 1491.2 mm.
  • 1956: matched soi, iod; differed antecedent_mm; wet-season outcome 1331.0 mm.

Euclidean distance on z-scored [ONI SON–DJF, SOI Sep–Feb, IOD ASO–NDJ, previous wet-season rainfall]. Equal weights. No SST fields, MJO or soil moisture.

  • · Scalar indices are not a substitute for field similarity.
  • · No universal percentage is reported because the distance has not been independently validated.
  • · Closest years can still produce widely different rainfall if a cyclone or monsoon burst occurs.