Performance of Major Flare Watches from the Max Millennium Program (2001-2010)

TL;DR

This study reviews the performance of the Max Millennium Program's Major Flare Watches over nearly a decade, highlighting their effectiveness in forecasting X-class solar flares and emphasizing the importance of coordinated multi-instrument observations.

Contribution

It provides a comprehensive analysis of MFWs' operational performance and their success in predicting major solar flares, offering insights for improving space weather forecasting.

Findings

56% of >X1 flares were detected by MFWs

MFWs had a 6.5% duty cycle over the study period

Forecast skill score (TSS) was 0.500, comparable to NOAA predictions

Abstract

The physical processes that trigger solar flares are not well understood and significant debate remains around processes governing particle acceleration, energy partition, and particle and energy transport. Observations at high resolution in energy, time, and space are required in multiple energy ranges over the whole course of many flares in order to build an understanding of these processes. Obtaining high-quality, co-temporal data from ground- and space- based instruments is crucial to achieving this goal and was the primary motivation for starting the Max Millennium program and Major Flare Watch (MFW) alerts, aimed at coordinating observations of all flares >X1 GOES X-ray classification (including those partially occulted by the limb). We present a review of the performance of MFWs from 1 February 2001 to 31 May 2010, inclusive, that finds: (1) 220 MFWs were issued in 3,407 days considered (6.5% duty cycle), with these occurring in 32 uninterrupted periods that typically last 2-8 days; (2) 56% of flares >X1 were caught, occurring in 19% of MFW days; (3) MFW periods ended at suitable times, but substantial gain could have been achieved in percentage of flares caught if periods had started 24 h earlier; (4) MFWs successfully forecast X-class flares with a true skill statistic (TSS) verification metric score of 0.500, that is comparable to a categorical flare/no-flare interpretation of the NOAA Space Weather Prediction Centre probabilistic forecasts (TSS = 0.488).