Material from: Linus

1. Overview

During 5–6 June 2026, Esperanza station recorded maximum temperatures of 15.4°C and 13.4°C, respectively. Both values exceeded the previous June record of 13.3°C, set on 12 June 1998. The 1991–2020 daily maximum temperature normal for Esperanza in June is around −6.2°C, so this was an extremely anomalous event (from Paola Rodriguez Imazio).

2. Analyses and Observations

2.1 Event Definition

Here we will focus on 3-day mean temperature on 5-7 June for the Esperanza station (63.4S, 57.0W).

2.2 Analyses

Link to Weather Replay:

The plots below show analyses of MSLP and 6 hour rainfall from 3 June 00UTC to 8 June 00UTC, every 12th hour.

The plots below show analyses of z500 and T850 from 30 May to 8 June, every 24 hour.

2.3 Observations

2.4 Climatological perspective

3. Forecasts

3.1 Data assimilation and observation usage

3.2 Single Forecasts for the event based on 00UTC forecasts (defined in Section 2.1)

Observations and analysis for the event

Control forecast (IFS 9-km resolution)

The plot below shows time-series of IFS control forecast from 5 June and the observations from Esperanza.

DestinE (IFS 4.4km resolution)

AIFS-single (AIFSv1.0 ~0.25 resolution)

AIFS-ENS control (~0.25 degree resolution)

3.3 Ensemble distribution

EFI (based on IFS 9-km ensemble)

The plots below show the Extreme Forecast Index for 3-day mean temperature valid 5-7 June.

The plots below show the Extreme Forecast Index for 3-day mean integrated water vapour flux valid 5-7 June.

Forecast Evolution plot

3.4 Sub-seasonal forecasts

3.5 Comparison with other centres

4. Hazard Forecasts

5. Dedicated Experiments

6. Event Summary

6.1 Good and bad aspects of the forecasts for the event

6.2 Experience from general performance/other cases

7. Additional material