Material from: Linus
1. Overview
During the last days of June and beginning of July Argentina (and Uruguay) was hit but unusually cold temperatures.
https://www.infobae.com/sociedad/2025/07/01/como-sigue-la-ola-polar-rigen-nuevas-alertas-por-bajas-temperaturas-en-todo-el-pais/
https://www.lanacion.com.ar/clima/ola-polar-en-argentina-hasta-cuando-durara-nid30062025/
https://www.infobae.com/america/ciencia-america/2025/06/30/alerta-por-frio-intenso-manana-podria-registrarsla-temperatura-mas-baja-del-ano-en-el-amba/
https://www.independent.co.uk/news/world/americas/uruguay-cold-snap-state-emergency-b2778071.html
2. Analyses and Observations
2.1 Event Definition
Currently based on the 3-day mean temperature 30 June - 2 July in a 0.25 degree box in Buenos Aires (34.7S, 58.75W).
2.2 Analyses
The plots below show analyses of T850 and z500 from 26 April to 2 May.
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
(Do be added after the event.)
Control forecast (IFS 9-km resolution)
DestinE (IFS 4.4km resolution)
AIFS-single (AIFSv1.0 ~0.25 resolution)
AIFS-CRPS ensemble (~0.25 degree resolution)
3.3 Ensemble distribution
EFI (based on IFS 9-km ensemble)
Forecast Evolution plot
Legend:
Observation - green hourglass
Analysis - green dot
ENS CF - red dot
AIFS-single - cyan dot
ENS distribution - blue
AIFS-ENS distribution - pink
ENS m-climate - cyan
ENS m-climate maximum - black triangle
3.4 Sub-seasonal forecasts