Operational statistical consensusTrack + intensity0–120 hours

A smarter way to combine the forecast field.

STRIKE SuperEnsemble transforms a diverse set of independent tropical cyclone forecast aids into three transparent consensus techniques. It is built to reduce individual-model noise, counter persistent directional and intensity biases, and exploit the fact that different aids often make different errors.

3independent STRIKE techniques
12 hforecast output interval
AL / EPbasin-specific training
Error cancellation in practiceRepresentative guidance envelope with increasing spread by lead time
STATISTICAL BLEND
GUIDANCE ENVELOPE120 H Representative tropical cyclone guidance spaghetti plot A dense family of independent model guidance tracks begins near a common analyzed position at lower left, then gradually diverges toward the upper right. The STRIKE consensus remains near the center of the guidance envelope. AVNI HFAI EMNI GDMI HMNI UKXI CTCI STRK 0 h 48 h 96 h 120 h
STRIKE consensusRetained, corrected, normalized contributors
Independent aidsDifferent structures, strengths, and error signatures
Common signalConsensus seeks the stable center of the forecast field
System overview

One path from forecast concept to verification.

STRIKE—short for Statistically-Tuned Real-time Integrated Kinematic Ensemble—turns diverse tropical cyclone guidance into one statistically refined, continuously verified forecast signal.

Understand the forecast signal

Begin with why combining independent guidance can be more stable than relying on a single aid, how disagreement is handled, and what STRK and STRR represent, along with the AI-only STRA technique now in development.

Continue to the techniques →

Follow the statistical system

Continue directly into basin- and horizon-specific weighting, historical bias estimation, robust screening, spherical averaging, issuance controls, and leakage-resistant replay.

Continue to the methodology →
How consensus helps

From a noisy forecast field to one coherent signal.

The core idea is simple: strong forecast aids do not fail in exactly the same way. When their errors differ in direction and magnitude, a disciplined statistical blend can let those errors offset one another while retaining the shared forecast signal.

STEP 01

Collect independent guidance

Use eligible track and intensity aids that are actually present for the storm and cycle.

STEP 02

Apply learned corrections

Reduce recurring along-track, cross-track, and intensity tendencies supported by historical samples.

STEP 03

Remove extreme departures

Use robust statistics to reject members that sit too far outside the current guidance cluster.

STEP 04

Rebalance the survivors

Renormalize available weights and cap any one contributor so the product remains a true consensus.

STEP 05

Publish a cycle-pure forecast

Create 12-hour track and intensity points through 120 hours, with a full machine-readable audit trail.

The STRIKE family

Three consensus techniques.

STRK is the adaptive operational consensus, STRR isolates the effect of raw performance weighting, and STRA extends the framework to an AI-only contributor set now being developed for 2027.

Control
STRR
STRIKE Raw

A cumulative raw-performance-weighted control. It uses the same historical sample, common frozen bias field, and robust production builder as STRK, but removes baseline shrink and the walk-forward adoption gate so the effect of the weighting philosophy can be isolated.

  • Raw performance weighting
  • Common bias + production builder
  • No STRK adoption gate
In development
STRA
STRIKE AI
Coming in 2027

A corrected consensus built exclusively from eligible artificial-intelligence forecast techniques. Development and training will use AI-guidance performance collected during the 2026 tropical-cyclone season.

  • AI-only contributor pool
  • Track and intensity correction
  • 2026 data for 2027 evaluation
Why consensus can work

Errors can cancel. Shared signal remains.

A model that runs too fast can partially offset one that runs too slow. A right-of-track tendency can partially offset a left-of-track tendency. The blend is most valuable when its contributors are skillful but not perfectly correlated.

Individual-aid view

Each point represents a different forecast aid. Their departures from truth are substantial, but they are not aligned in the same direction.

Robust-consensus view

After correction, screening, and weighting, the retained field can locate a more stable center than any arbitrary single member.

consensus = Σ(corrected member × normalized weight)
Technical methodology

From historical training to live production.

Explore how STRIKE learns from completed seasons, processes each forecast cycle, and preserves a valid walk-forward test.

1. Eligible guidance is explicit

STRIKE is built from configured, independent forecast aids present in the current storm cycle. Existing consensus products are excluded from the member pool so the system does not recursively blend a blend. Individual GEFS members are also excluded from the STRIKE member set.

≥ 5retained contributors required
12 hforecast point spacing
120 hmaximum forecast tau

2. Track and intensity are separate statistical problems

A model can be excellent at track and mediocre at intensity, or vice versa. STRIKE therefore resolves two independent weight tables and two independent correction systems at each forecast point.

  • Track: corrected latitude/longitude positions are combined with a weighted spherical mean.
  • Intensity: corrected maximum-wind forecasts are combined with a weighted mean and rounded to the nearest 5 kt.
  • Pressure: when available, pressure is averaged from the retained intensity contributors using their normalized weights.

3. The statistical cells change with basin and lead time

Weight and bias behavior is organized by basin, component, and forecast horizon. Central Pacific cases map into the East Pacific profile.

SHORT0–48 hours
MEDIUM60–96 hours
LONG108–120 hours

This structure reflects the practical reality that member skill and error character can change between basins and across the forecast period.

4. Independence is a design constraint

The target is complementary information, not a popularity vote. Consensus aids already containing several models are kept out of the construction pool, while eligible deterministic and ensemble-mean aids can contribute according to the configured tables. This preserves clearer attribution and reduces hidden double counting.

1. Finalized history becomes a case matrix

Each training case is indexed by storm, initialization cycle, and forecast hour. Eligible member forecasts are matched to best-track truth, yielding track error, signed intensity error, along-track error, and cross-track error. Duplicate aid/case records are resolved before optimization.

The trainer uses only independent aids configured for the applicable basin, component, and horizon cell.

2. Candidate weights reward skill and usable availability

For each aid, recency-weighted mean absolute error is converted into a quality score. Availability contributes a smaller positive term so an aid that is skillful but rarely present does not receive the same practical influence as an aid that is both skillful and consistently usable.

quality(aid) = (1 / recency-weighted MAE)1.2 × availability0.25

Stability controls

  • Historical seasons decay exponentially according to a configurable half-life.
  • Candidate weights are blended 50/50 with the baseline table.
  • Weights below 2.5% are pruned.
  • The implemented trainer caps GDMI at 10% during candidate-weight derivation.
  • If fewer than three weighted aids remain, the baseline table is retained.

3. Optimization must survive a season-by-season walk-forward test

For each held-out season, the candidate weights are trained only on earlier seasons, then compared with the baseline on the held-out year. A new table is adopted only when its aggregate walk-forward skill reaches the configured minimum and it beats the baseline in at least half of tested seasons.

0.25%minimum walk-forward skill
50%minimum positive seasons
3minimum scoring contributors

Candidate files are generated for review; the trainer does not silently promote them to operations.

4. Bias coefficients are recency-weighted, trimmed, and shrunk

Track bias is estimated in a verifying-motion-relative coordinate frame: along-track and cross-track. Intensity bias is forecast maximum wind minus verifying maximum wind. Each tail of the historical error distribution can be trimmed before the weighted mean is calculated.

shrunk bias = trimmed recency-weighted bias × N / (N + K)

Only cells meeting the minimum sample requirement become eligible. Operational correction subtracts the eligible coefficient, multiplied by a component/horizon application strength, from the member forecast before consensus construction.

5. Historical replay is cumulative and leakage-resistant

The first available season begins from one fixed equal-weight seed for the historical control framework. After each season is complete, the next season is built only from information that would have existed at that boundary: STRK is cumulatively re-estimated with its adopted and shrunk performance method, while STRR is cumulatively re-estimated from raw performance with zero baseline shrink and no adoption gate.

A common cumulative bias field is estimated from completed prior seasons and frozen for the replay techniques during the next season. This keeps the comparison focused on weighting behavior rather than giving one technique a different correction history.

  • No future-season information enters an earlier replay forecast.
  • Weights and bias coefficients are frozen within each replay season and update only after season completion.
  • The same production builder used operationally constructs STRK and STRR replay tracks.
  • The replay is skipped when source signatures, configuration, builder source, and required artifacts are unchanged.

1. Readiness is governed by track attendance

The issuance gate checks the ranked track contributors in short, medium, and long horizons. Missing top-five track contributors receive a longer grace period than missing additional contributors. Intensity availability does not block issuance.

A member with a clean, contiguous track that legitimately ends before a later horizon is marked reduced-horizon and excluded from that later attendance gate, rather than treated as late.

2. Eligible bias is removed member by member

At each nonzero tau, the builder resolves the basin/component/horizon coefficient for each contributor. Track correction translates signed along/cross bias into an earth-relative displacement using the member’s local heading. Intensity correction subtracts the shrunk signed bias and constrains the result to a physically bounded range.

Tau zero remains an anchor and is not bias-corrected.

3. Robust screening protects the blend from extreme departures

Track

The builder finds a robust center from median latitude and longitude, measures each corrected contributor’s great-circle distance from that center, and computes a median absolute deviation. The rejection threshold is the larger of 2.75 × MAD or a lead-time-dependent floor that expands from 175 n mi early to 625 n mi at 120 hours.

Intensity

The same 2.75 × MAD structure is used around the median intensity, with a minimum rejection threshold of 25 kt.

If fewer than five contributors survive, that component is not published for the tau.

4. Available weights are renormalized without allowing dominance

Configured weights are renormalized across the retained contributors. If any contributor would exceed 45% after missing members or outliers are removed, iterative water-filling caps that member and redistributes its excess proportionally among the others.

0 ≤ normalized member weight ≤ 0.45    and    Σ weights = 1

5. Published forecasts are immutable and auditable

Each issued technique contains points every 12 hours through 120 hours. The archive records resolved weight tables, correction details, rejected and retained members, normalization decisions, readiness status, source hashes, coefficient hashes, and final product hashes.

Once issued for a cycle, the package can be locked rather than silently changing as late source data arrives.

Operational sequence

Statistical rigor without a heavy compute stack.

The expensive work is historical analysis performed periodically. Live construction is compact numerical processing over a small set of forecast points—well suited to a modest virtual machine rather than specialized hardware.

Source ingestRead cycle-pure forecast guidance and identify available configured aids.I/O bound
Correction + screenApply frozen coefficients and robust outlier rules at each tau.small-vector math
Consensus solveRenormalize weights, compute spherical track means and intensity means.O(aids × taus)
Audit + publishHash, archive, and expose the issued technique for dashboards and verification.compact JSON
Computational profile

Designed to run efficiently on ordinary infrastructure.

STRIKE’s live workload consists primarily of dictionary lookups, robust summary statistics, great-circle calculations, small weighted reductions, and JSON serialization. It does not require a numerical weather prediction model, GPU cluster, or large in-memory inference service.

Virtual-machine friendly by design

A standard virtual machine can execute the cycle builder because the system consumes existing forecast aids rather than integrating the atmosphere itself. Historical training uses tabular arrays and can also run on commodity CPU resources.

Live CPU demandLow
Live memory demandLow
Specialized hardwareNone required
Bars are architectural characterizations, not benchmark measurements. Actual use depends on file volume, runtime, and hosting configuration.
operational_cycle.pyconceptual
for tau in range(0, 121, 12): members = select_available_aids(tau) corrected = apply_frozen_bias(members) retained = robust_outlier_screen(corrected) weights = normalize_and_cap(retained) track = weighted_spherical_mean(weights) intensity = weighted_mean(weights) audit(tau, retained, rejected, weights) publish_cycle_if_valid()
Transparent verification

Performance belongs in the open.

Verification is presented in two layers: a finalized 2019–2025 cumulative walk-forward replay and the provisional live season. Historical scorecards use NHC-style homogeneous comparisons at each standard forecast period, so every displayed aid in a column is evaluated on the same storm, cycle, and forecast-hour cases.

Historical walk-forward validation

STRK and STRR are evaluated through a true walk-forward replay. Training advances only after each season ends, preventing future information from improving past forecasts.

Embedded finalized archive
2019–2025walk-forward seasons
275completed storms
112track ranking cells
8standard forecast periods
AL + EPbasin-specific verification

Strong automated-aid track placement

Across 112 season, basin, and forecast-hour rankings, STRK finished in the automated top five 99 times, while STRR did so 93 times. STRR recorded the most first-place finishes with 17, illustrating the upside of raw performance weighting in favorable seasons.

The weighting result is nuanced

The replay does not support a claim that one weighting approach always wins. Raw-performance STRR produces the greatest upside in favorable seasons, while STRK remains highly stable, placing in the automated top five in 88% of track rankings.

Selected pairwise comparisons

STRK is placed alongside EMNI, OFCI, and FSSE using cases available to both techniques. Mean errors and relative differences are shown together so the scale of each result remains visible. Each comparator has its own verification universe.

OFCL is retained as a different class of benchmark

OFCL is the NHC official forecast, not a peer automated model aid. It remains visible in the scorecard because it is operationally important, while the placement findings above use the automated-aid peer rank so guidance can be compared on a more like-for-like basis.

Positive differences indicate lower STRK error. Negative differences indicate higher STRK error and are shown neutrally. Values that round to 0.0% are reported as a tie. EMNI and OFCI use embedded pairwise records; FSSE is aggregated from the homogeneous seasonal scorecard. Results from different comparator cards are not directly comparable.

Season
Basin
Metric
Scorecard format
Official benchmark
Preparing horizon means…
Each horizon value is calculated in the browser as the arithmetic mean of the available homogeneous forecast-period errors in that band. Rows are sorted from lowest to highest short-range mean by default; click a horizon heading to sort that band.
STRIKE techniqueOFCL official benchmarklowest mean error in column
Scientific posture

What STRIKE is—and what it is not.

A credible public forecast system should explain its scope, controls, and limitations as clearly as its strengths.

It is a statistical post-processing model

STRIKE does not simulate the atmosphere. It statistically combines and corrects existing tropical cyclone guidance using finalized historical verification and cycle-specific availability.

  • Transparent contributor logic
  • Frozen operational coefficients
  • Independent controls for comparison

It is not official warning guidance

STRIKE is an experimental decision-support and research product. Official forecasts, watches, warnings, and public safety instructions remain the responsibility of the appropriate meteorological agencies.

  • Use alongside authoritative products
  • Expect provisional live verification
  • Do not infer certainty from consensus
Project origin

About STRIKE.

An operationally motivated statistical model developed to support decisions involving forecast uncertainty, employee safety, infrastructure exposure, and continuity of operations.

Operational origin

STRIKE SuperEnsemble is an independently developed statistical tropical-cyclone consensus system created by Adam Hazell, an engineer in the radio-frequency and broadcast field.

The system originated from the need to evaluate forecast risk across a geographically distributed network of broadcast infrastructure. Operational decisions included prioritizing site preparation, positioning technical personnel and recovery resources, protecting employee safety, and maintaining continuity at facilities representing multimillion-dollar infrastructure investments.

The decision problem

This application required more than a single deterministic forecast or a binary interpretation of the forecast cone. The relevant decision space included model disagreement, track uncertainty, expected intensity, forecast timing, site exposure, and the comparative consequences of underestimating or overestimating risk at different locations.

STRIKE applies an engineering and statistical framework to that problem. It evaluates multiple forecast aids using historical verification, separates performance by forecast horizon and basin where supported, applies defined weighting and correction procedures, and generates consensus tracks and intensities from the available guidance.

Relevant development experience

The development of STRIKE was informed by prior work creating internal weather-monitoring and decision-support applications for technical operations. That experience included the integration of meteorological datasets, development of site-specific risk displays, and conversion of complex forecast information into operationally useful guidance.

The model is designed so that its inputs, calculations, and verification results can be inspected rather than treated as an opaque forecast product.

AI-assisted engineering

AI-assisted development tools were used extensively during software construction and evaluation. Their role included accelerating code development, processing historical archives, constructing tests, comparing model configurations, and supporting backtesting and hindcasting.

The forecast methodology itself remains deterministic and reproducible: defined inputs are processed through documented statistical procedures to produce the published output. AI tools accelerated development and analysis; they do not independently generate STRIKE forecasts.

Research and collaboration

Priorities for external evaluation.

The next stage of the STRIKE SuperEnsemble is focused on independent evaluation, improved access to upstream forecast aids, and collaboration with the meteorological community. The objective is not simply to demonstrate favorable retrospective results, but to determine whether the methodology remains useful, stable, and operationally defensible under real-time forecasting conditions.

Data access

Timely access to forecast guidance

Research access to forecast aids at or near native model availability would allow the STRIKE SuperEnsemble to operate before those records appear in the public A-deck. Earlier availability is necessary for genuine real-time testing within the same decision window faced by operational forecasters.

The highest-priority need is ECMWF deterministic tropical-cyclone guidance, preferably EMXI, together with other major numerical and AI-derived aids that are not consistently available through public real-time datasets.

Verification

Independent annual evaluation

Annual verification of STRIKE SuperEnsemble ATCF records is sought for storms in which the system produced real-time forecasts. Evaluation using NHC procedures and case definitions would permit fair comparison with official forecasts and recognized operational aids.

The purpose is to establish an external performance record based only on forecasts issued before the verifying outcome was known, separate from internal hindcasting and development results.

Scientific review

Methodological and operational assessment

Technical review by tropical-cyclone researchers and operational forecasters would provide scrutiny of the STRIKE SuperEnsemble training design, weighting methodology, bias correction, case selection, and safeguards against information leakage.

A longer-term objective is experimental evaluation within the NHC forecast-development process. Consideration for inclusion should follow only if independent real-time verification demonstrates stable and measurable value beyond existing guidance.

Forecast communication

A more stable public guidance signal

A further research question is whether a verified superensemble can improve public interpretation of tropical-cyclone guidance. Individual model tracks and intensity forecasts can fluctuate sharply between cycles, drawing attention to short-term movement rather than the broader forecast signal.

The STRIKE SuperEnsemble is designed to reduce independent forecast errors through statistical consensus and may provide a more stable representation of track and intensity evolution. Any public-facing use should remain supplemental to official NHC products and should be evaluated for both forecast performance and communication effectiveness.

Technical report: This paper is the formal STRIKE SuperEnsemble research submittal describing the methodology, verification framework, and current results.Download Technical Report (PDF)
Frequently asked questions

Understanding STRIKE.

Straightforward answers about the methodology, forecast process, and performance record.

Why not just use the best individual model?
The identity of the “best” aid changes by basin, forecast horizon, storm, cycle, and metric. STRIKE reduces dependence on a single failure mode and can benefit when member errors are complementary. It does not assume the consensus wins every case.
Does STRIKE use the same weights everywhere?
No. Track and intensity use different tables, and the tables are separated by Atlantic/East Pacific profile and short/medium/long forecast horizon.
How does STRK differ from a simple average?
STRK can use historically trained performance weights, availability adjustment, member-specific bias correction, robust outlier rejection, dynamic renormalization, and a 45% operational dominance cap. STRR provides the public comparison against raw performance weighting.
Can a late or missing model stop the forecast?
The readiness gate provides limited grace passes, prioritizing missing top-five track contributors. Cleanly reduced-horizon guidance is not treated as missing in later horizons. After issuance, the product can be locked for cycle integrity.
How is overfitting controlled?
The trainer blends candidate weights with a baseline, prunes small weights, requires minimum samples, shrinks bias estimates, tests candidate weights in held-out seasons, and generates candidates for review rather than silently promoting them.
What did the historical replay actually show?
The 2019–2025 homogeneous replay shows that track is the strongest result. STRR recorded the most first-place finishes, while STRK remained in the automated top five in 99 of 112 season, basin, and forecast-hour rankings. The result is deliberately nuanced: the raw and adopted weighting approaches each perform differently across seasons and forecast horizons.
Why is OFCL treated separately in the historical findings?
OFCL is the NHC official forecast and is operationally important, so it remains visible in the scorecard. The placement findings use the automated-aid peer rank because the purpose is to compare model and consensus guidance on a like-for-like basis. The scorecard toggle can hide or restore the OFCL benchmark row without changing the homogeneous case universe.
Why can it run on a small virtual machine?
The live system performs post-processing over a limited number of aids and forecast points. It is not running an atmospheric model. Its core operations are small weighted statistics, geometry, filtering, hashing, and file publication.
STRIKE SUPERENSEMBLE

A clearer signal from the forecast field.

Explore current verification, understand the forecast approach, or review the methodology behind STRK, STRR, and the developing STRA technique.