The Aemet warned on October 29 of maximum rainfall in Valencia of 200 l/m2 when it reached 772

With an aseptic and technical nature, Aemet collects the “evolution of the atmospheric situation that gave rise to this extraordinary event”, as well as a “chronology of predictions and warnings of adverse meteorological phenomena issued by Aemet for the main affected areas.” This detailed report, which occupies a third of the report, seems to be a response to the insinuations of the president of the Valencian Community, Carlos Mazón, who in his appearance before ‘les Corts’ offloaded a good part of the responsibility on the State Agency for Meteorology and in the Júcar Hydrographic Confederation, two organizations dependent on the Ministry for the Ecological Transition and Demographic Challenge (Miteco).

Regarding the justification of the predictions and warnings, also questioned by some sectors, the Aemet makes a lengthy chronology that goes back to Saturday, October 20. For that date is when he made his first prediction, in which, “with high uncertainty” as they acknowledge, they stated that “intense and abundant rainfall on the eastern façade is not ruled out.” In the following days they became more specific about the area and even the volume of rainfall.

It is on Saturday the 26th when the first explicit reference is made to Tuesday the 29th, “the day on which the largest accumulations of the entire episode are expected.” However, the area remains imprecise, since the information note from that day speaks of “the eastern center of the peninsula, the southern plateau and, even with greater accumulations, Alborán and the peninsular Mediterranean.”

On Sunday the 27th, Aemet issued a “special notice” in which it already stated that by Tuesday “it is likely that points in the Valencian Community and Murcia will exceed 150 mm in 24 hours.” On Sunday and Monday this special warning was renewed, specifying the area more but always with the forecast of rain locally between 150 and 180 mm between 12 and 24 hours. An amount very far from what would later occur in the area that feeds the Magro and Poyo flows, where it would exceed 325 liters per square meter.

It is already the same day the 29th when the Aemet issues several warnings that raise the meteorological risk to orange or red level. For the area of ​​Alcaraz and Segura (Albacete), where the Letur floods occurred, the orange level remained throughout the day. However, in the province of Valencia the levels changed depending on the area and the hours, according to how the situation evolved.

Thus, in the Northern Litoral area, which includes both Turís and Cheste, where it rained the most, and the towns in the orchard of Valencia where the greatest personal and material damage occurred, the orange alert was set at 7:52 for rain. from 40 to 140 mm. At 9:41 the warning was raised to the red level, “expecting accumulations of 90 and 180 mm in one and twelve hours until 6:00 p.m., at which time they would be lowered to the yellow warning levels.” It was the information that led Mazón to publish in X that the situation would improve from that time on, in a post that he would later delete.

However, at 5:49 p.m. there was an update that extended the red notices until 8:00 p.m., which Mazón could no longer see, as he was unreachable at the well-known meal at the El Ventorro restaurant, a place without coverage. At 7:47 p.m. the warning was extended until 10 p.m. The problem is that in the towns closest to the coast and that suffered the overflowing of the Poyo ravine, it hardly rained all day (in Paiporta it fell less than 5 l/m²), so the red alert for heavy rainfall instead The floods confused the neighbors and caused uncertainty that could have been fatal for some of them, who tried to save their cars from the underground garages or their belongings from their basements.

For the Aemet, the red level implies that “the meteorological risk is extreme (unusual meteorological phenomena, of exceptional intensity and with a very high level of risk for the population)” and according to its website the recommendation for citizens is to take “measures preventive” and act “according to the instructions of the authorities.” In this case, they only received the EsAlert message at 8:12 p.m. that also insisted on the “heavy rains” and as a preventive measure proposed avoiding “any type of travel in the province of Valencia.” By then, most of the towns that the Poyo ravine crosses were already flooded.

The ambiguity of these messages, together with the fact that the Aemet forecasts spoke of a maximum of 180 l/m² (in the last update at 7:47 p.m. it was raised to 200), when 350 were exceeded in a large area and reached more than 600 in Chiva and 772 in Turís, call into question the effectiveness of the alerts that the state agency launched on October 29 and which is in charge of review in your report.

Record precipitation records

The Aemet report also includes the most notable precipitation records observed both by the organization’s network of stations and by the SAIH of the Júcar Hydrographic Confederation, as well as other observation networks of official and amateur organizations. Of all the measurements, the one at the Turís station (Valencia) stands out, which “with extraordinarily high intensities” reached the new Aemet accumulated records that day, in one, six and twelve hours.

Thus, the maximum data for one hour, 185 mm, triples the value of 60 mm used for the definition of torrentiality and is 26 mm higher than the previous record, previously observed in Vinaroz (Castellón) on October 19, 2018. In Regarding the values ​​of six and twelve hours (621 and 720 mm respectively), they double the most extreme values ​​recorded in Alpandeire (Málaga) on October 21, 2018. Regarding the accumulated in one day, the Turís station registered 772 l/m², when the annual average in the population is 475 l/m².

It is striking that the Aemet report includes rainfall data for Turís, with 772 l/m2, followed by Utiel, with 243 l/m2, two towns located in the Magro River basin, and does not make any reference to the rain gauges installed in the areas that discharge their waters into the Poyo ravine, which would ultimately cause the majority of fatalities and material damage. To give an example, in Chiva, where the ravine begins, 600 l/m2 were exceeded according to other measurements.

Although it is not included in the report, a map is especially significant – also disseminated this Friday on the social networks of Aemet Comunidad Valenciana – that relates the accumulated precipitation with the three channels that caused problems: that of the Magro river, that of the Poyo ravine and the Turia (which did not overflow but forced the evacuation of several districts in Valencia). It is curious how, while Cecopi’s attention was focused on the flooding in Utiel and the possible collapse of the Forata dam -located in areas where the rainfall was at 350 l/m²-, the rainfall was close to 800 l /m² were located in the area between Turís and Chiva, which drain respectively into the Magro, although downstream of the reservoir, and into the Poyo ravine, where the greatest material damage and the highest number of victims finally occurred.

Despite the data provided, the Aemet is unable to specify whether it is the worst DANA suffered since there are records and limits itself to pointing out that “it is still early to analyze in the climate context the position in the ranking that this situation would occupy. in terms of accumulated precipitation achieved and the impacts caused. However, it does maintain that “in comparison to previous historical situations, so far everything indicates that it is the largest flood caused by a DANA in the 21st century in our country, comparable with other historical events that occurred in the Valencian Community during the decades of the 50s and 80s of the last century”, in a reference to the flood that devastated Valencia in 1957 and the swamp of 1982 that, after the failure of the Tous dam, affected several towns in the region of La Ribera.