Meteorological Report No. 34

Sara is downgraded to a tropical depression as its influence over Costa Rica continues to diminish

Sunday, November 17, 2024

4:00 pm

Diagnosis: Tropical depression Sara continues to weaken as it moves over land north of Central America. According to current projections, this system will continue to move towards the Gulf of Mexico and will eventually dissipate during the course of Monday.

Over Costa Rica, satellite images and wind data show the persistence of a weak southwesterly flow associated with this system over central and northern Guanacaste. This condition favors mostly cloudy skies with scattered light to moderate rains in the province. The maximum amounts recorded in the area are between 5-21 mm in the last 6 hours.

In addition, local factors such as high daytime temperatures and the formation of breeze fronts have generated variable rainfall including storms and isolated heavy downpours in the Central Valley, Northern Zone and mountainous areas of the Caribbean and Central and South Pacific. Maximum amounts recorded between 12-45 mm in the last 6 hours.

Forecast: Tonight, the southwesterly flow over Guanacaste is expected to weaken as Sara continues its movement north and continues its dissipation process. During this night period, the country will be out of its influence.

On the other hand, convective nuclei due to the formation of breeze fronts are observed developing in the North Zone, Mountainous Zones of the Caribbean and around the mountain ranges of Guanacaste and Tilarán. Due to this, variable rainy activity is expected, including heavy showers with localized storms, in these areas at least in the next 2-3 hours. In addition, cloudiness is expected to move towards the Central Valley, which will maintain intermittent rains in almost the entire region during the same period.

Apart from the showers around the Guanacaste and Tilarán mountain ranges, the North Pacific will maintain scattered rains in the center and west of the region, while in the Central and South Pacific showers are expected mainly in mountainous areas

The estimated accumulations by region in the next 12 hours are detailed below:

North Pacific: ranges between 15 mm and 40 mm, with higher maximums located in the mountain ranges.
Central Pacific: ranges between 10 mm and 30 mm, with maximums of 50 mm.
South Pacific: ranges between 10 mm and 30 mm, with maximums of 50 mm near the mountains.
Central Valley: ranges between 15 mm and 30 mm, with maximums between 50 mm.
North Caribbean and South Caribbean: ranges between 15 mm and 30 mm, with maximums of 50 mm in the mountains.
Northern Zone: ranges between 15 mm and 40 mm, with a maximum of 70 mm in the mountains.

It should be noted that higher amounts can be recorded in a localized manner in each respective region.

⚠ Attention: The rainy pattern due to the indirect influence of this tropical cyclone will continue until this Sunday in the North Pacific. The rest of the country is outside the influence of Sara, however, the occurrence of isolated showers in the afternoon is likely due to factors inherent to the season.

Warning: High soil saturation remains in much of the country, with saturation levels between 90% and 100%. Therefore, there is a high probability of flooding in vulnerable places, mainly in the low regions of the Pacific, landslides in the mountains of the Pacific, in the west and east of the Central Valley, in the Northern Zone, the Tilarán Mountain Range and those in the west of the Caribbean.

Due to the above, the IMN recommends:

Pay attention to overflowing streams and rivers with high flows.
Be alert in places prone to landslides.
Prevention against electrical storms and seek shelter in a safe place in case of occurrence or perception of strong gusts of wind near storm clouds, due to the possible fall of tree branches, power lines, among others. These gusts can reach 80 km/h in some isolated cases.
Stay informed through social networks, Twitter: @IMNCR, Facebook: Instituto Meteorológico Nacional CR and the WEB Page: www.imn.ac.cr

Next report: Sunday, November 17 at 10 p.m.

Roberto Vindas

Meteorologist

DMSA-IMN

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