| Tropical Storm Pilar | |
| Formed: | October 28, 2023 |
| Dissipated: | November 6, 2023 |
| Winds: | 50 |
| Pressure: | 996 |
| Fatalities: | 4 indirect |
| Damage: | 45000000 |
| Areas: | Central America (especially El Salvador) |
Tropical Storm Pilar was an erratic tropical cyclone that brought heavy rainfall to Central America, though it did not make landfall. The nineteenth tropical depression and sixteenth named storm of the 2023 Pacific hurricane season, Pilar formed on October 28, from the remnants of Atlantic Tropical Depression Twenty-One off the coast of Nicaragua and Costa Rica. After strengthening into a tropical storm, it took an east-northeastward track toward Central America, but then turned westward and moved away from land. Shear stopped the storm from strengthening and it became a remnant low on November 5, far away from the Baja California peninsula.
Heavy rains from Pilar fell upon Central America. Flash flooding there resulted in 4 deaths and damage estimated at $45 million USD.
On October 25, a broad area of low pressure, partially related to the remnants of Tropical Depression Twenty-One from the Atlantic basin, formed offshore Central America.[1] The low remained poorly defined and broad for a few days due to persistent easterly shear.[2] Then, after multiple bursts of central convection, the circulation became well defined enough for the system to be designated Tropical Depression NineteenE on October 28.[3] The depression moved little initially, before starting to move slowly east-northeastward the following day. Deep convection then formed over the center, and it's low-level circulation tightened, allowing for the system to strengthen and become Tropical Storm Pilar around 00:00 UTC on October 30, about west-southwest of San Salvador, El Salvador.[2] Pilar proceeded to move slowly east-northeastward,[4] while experiencing erratic bursts of convection and battling moderate easterly wind shear.[5] Pilar reached a peak intensity of early on November 1, about off the coast of El Salvador. Around this time, a strong cold front approaching from the northwestern Caribbean Sea and its associated mid-level ridge began redirecting the storm, which turned sharply northward and then westward, out to sea.
The system moved quickly west-southwestward the following day, weakening along the way due to an influx of drier air brought about by the Gulf of Tehuantepec gap-wind flow it was embedded within.[2] The storm slowed down on November 5, and turned northwestward in response to a mid-level trough extending southwest of the Baja California peninsula.[6] Later that day, Pilar became bereft of organized convection, and degenerated into a post-tropical remnant low at 18:00 UTC. It later opened up into a trough late on November 7.[2]
A Tropical Storm Watch was issued on October 29 for the Pacific coast of El Salvador.[2] The government of El Salvador put the country on alert and declared a national emergency. School classes were cancelled across El Salvador, and around 100 shelters were prepared.[7] [8] The following day, a Tropical Storm Watch was issued from Puerto Sandino, Nicaragua, to the Honduras–Nicaragua border, and for the Pacific coast of Honduras.[2] Additionally, the government of Costa Rica issued an Orange Alert as the storm neared Central America on October 31.[9]
Heavy rainfall from Pilar inundated parts of El Salvador, Honduras, and Guatemala, flooding several rivers, which caused damage to homes, infrastructure, and crops.[2] [10] [11] Recorded rainfall totals were highest in southeastern El Salvador, where a total of 8.89 in (225.9 mm) was reported near Beneficio La Carrera.[2] Pilar caused four flood-related deaths. Three people in El Salvador drowned: a 24-year-old man in La Unión, a 57-year-old woman in the same municipality, and a 31-year-old man in Nueva Granada. The fourth death occurred in Honduras. Several hundred people in the two countries, as well as in neighboring Guatemala moved to shelters during the storm.[2] [10] [11] Pilar also brought heavy rainfall to western Nicaragua, displacing several families.[12] The Professional services firm AON estimated a total storm loss of $45 million.[2]