A tropical wave caused rounds of heavy showers and thunderstorms across the northwestern quadrant of Puerto Rico as well as eastern and southeastern portions of Puerto Rico.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS SJU wrote it up.
A tropical wave caused rounds of heavy showers and thunderstorms across the northwestern quadrant of Puerto Rico as well as eastern and southeastern portions of Puerto Rico.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Juan, PR wrote its last area forecast discussion before the first event at Oct 2, 11:26 AM AST, 3 hours 4 minutes earlier.
Area Forecast Discussion National Weather Service San Juan PR 1126 AM AST Sat Oct 2 2021 .UPDATE... No change to the inherited short term forecast and reasoning at this time. Tropical wave and associated moisture will continue to cross the region today into early Sunday, promoting a moist and unstable environment with favorable conditions for enhanced convective development. Recent TJSJ 02/12Z sounding suggests a PWAT value of 2.35 inches with the very moist layer and strong southeasterly low level winds. That said the potential for urban and small stream flooding will remain high, particularly across the interior and northern half of PR including the San Juan Metro. Ponding of water on roads and in poor drainage areas will also continue, with the heavy rains elsewhere. Mudslides will be possible in areas of steep terrain in PR where the soil remains saturated from previous days rains. A drying trend still expected late Sunday into Monday with the arrival of the Saharan dust and increasing easterly winds as the local pressure gradient tightens and low level moisture erodes. && .AVIATION UPDATE...No change to previous AVN discussion. Prevailing VFR, however a tropical wave will cross the region today into Sunday bringing SCT-BKN lyrs nr FL025...FL050...FL080 with SHRA/Isold TSRA psbl en route btw islands and over regional waters as well as VCSH/VCTS at most terminals during the rest of the period. Recent visible satellite imagery showed Saharan air layer with suspended Saharan dust particulates just east of the Lesser Antilles and approaching the region. && .MARINE update...No change to the previous marine discussion at this time. Moderate to locally fresh easterly to southeast winds will continue with choppy seas between 3 to 6 feet across much of the local waters and passages. Showers and isolated thunderstorms with brief gusty winds will continue across the local waters as a tropical wave crosses the region. && .PREV DISCUSSION... /issued 420 AM AST Sat Oct 2 2021/ SYNOPSIS...Unstable condtions with showers and thunderstorms will continue over the area today. A gradual drying trend is expected Monday and onwards as stability and winds increase. Saharan dust particles continue this way, and some haziness expected early the next week. SHORT TERM...Today through Monday... Doppler Radar and Satellite imagery detected showers and thunderstorms moving across the region due to a tropical wave. This wave moving across the islands will increase moisture and instability through at least Sunday. Therefore, expect enhanced convection, which could produce urban and small stream flooding and strong thunderstorms across Puerto Rico and the U.S. Virgin Islands. Soils are already saturated, and any persistent rain could trigger mudslides, especially during the afternoon hours. The lingering moisture associated with this wave will remain until tomorrow afternoon, resulting in a seasonal weather pattern driven by showers advection and sea breeze variations. A ridge pattern will build aloft, stabilizing the atmosphere and promoting sinking air aloft. In addition, a dry air mass with Saharan dust particulate will filter from the east by Sunday afternoon into next week. This air mass will result in hazy skies. The maximum temperatures will continue in the low 90s, with heat indices rising into the 100s degrees Fahrenheit, especially between 10 am and 4 pm, across urban and coastal areas. LONG TERM...Tuesday through Sunday... A mid to upper level ridge will hold across the local islands much of the forecast cycle with some weakening expected by the upcoming weekend. At lower levels, a surface high pressure north of the area will yield moderate to fresh easterly winds Tue-Wed, becoming gentle to moderate Thursday and onwards. Under ridge pattern aloft, precipitable water values are expected to remain below the normal range through at least Friday. However, as the ridge aloft weakens, moisture advection is then expected Sat-Sun. This pattern should keep a seasonable weather conditions, with mostly fair weather conditions and diurnally induced convection over western PR each afternoon. Breezy...Tue-Wed. Heat indices will be into the 100s with temperatures in many areas ranging from the upper 80s to lower 90s. Some haziness early in the cycle. AVIATION...SHRA/TSRA will move across the islands due to a tropical wave. This activity could impact terminals at times. Brief MVFR conditions will remain possible across IST/ISX and by 02/15z across JSJ/JBQ. TSRA will form across the Cordillera Central between 02/15-22z, causing mountain obscuration and producing frequent lightning. Winds will be light and variable overnight, increasing to 10 to 15 knots from the ESE-SE with sea breeze variations after 02/14z. MARINE...A moderate to fresh easterly wind flow will prevail across the local waters during the next several days. Scattered showers and isolated thunderstorms will continue from time to time today. Wind-driven seas of up to 8 feet will result in hazardous marine conditions early the next week. && .PRELIMINARY POINT TEMPS/POPS... SJU 89 78 91 77 / 60 50 40 30 STT 88 75 89 76 / 60 50 40 20 && .SJU WATCHES/WARNINGS/ADVISORIES... PR...High Rip Current Risk until 6 PM AST this evening for Northwest. VI...None. AM...None. && SHORT TERM...RAM LONG TERM....CS PUBLIC DESK...RVT
Perspectivas sobre las Condiciones Peligrosas del Tiempo Servicio Nacional de Meteorologia en San Juan PR 400 AM AST sabado 2 de octubre de 2021 AMZ710>745-PRZ001>013-030800- San Juan y Vecindad-Noreste-Sureste-Este Interior-Norte Central- Interior Central-Ponce y Vecindad-Noroeste-Oeste Interior-Mayaguez y Vecindad-Suroeste-Culebra-Vieques-Las aguas costeras cercanas y lejanas a la costa del Atlantico y Caribe- 400 AM AST sabado 2 de octubre de 2021 Esta Perspectiva sobre las Condiciones Peligrosas del Tiempo es para Puerto Rico y las aguas costeras adyacentes del Atlantico. .Dia Uno...Hoy y esta noche .Tronadas...Existe el potencial de tronadas aisladas con lluvia fuerte y rafagas de vientos esta tarde a traves de gran parte de Puerto Rico. Tronadas intensas sobre el interior pudieran producir granizo pequeno y rafagas de vientos fuertes. .Inundaciones...Lluvias fuertes podrian resultar en inundaciones urbanas y de riachuelos, asi como deslizamientos de tierra en areas de terreno empinado. .Vientos...Se esperan vientos sostenidos en exceso de 20 mph (17 nudos) a traves de sectores de las aguas mar afuera del Atlantico y Caribe, asi como los pasajes locales. .Oleaje...Se espera oleaje picado de hasta 6 pies a traves de sectores de las aguas mar afuera del Atlantico y Caribe, asi como los pasajes locales. .Corrientes marinas...Existe un riesgo alto de corrientes marinas para las playas de la costa noroeste de Puerto Rico. Un riesgo moderado continua para el resto de las playas orientadas hacia el norte y este. .Calor...Se esperan indices de calor entre 102 y 107 grados a traves de la mayoria de las areas urbanas y costeras. .Dias dos hasta el siete...domingo a viernes Se esperan aguaceros y tronadas en las tardes causando un riesgo elevado de inundaciones urbanas y de riachuelos mayormente para el interior de Puerto Rico. Se pronostica un aumento gradual de los vientos alisios para el domingo a temprano la proxima semana, resultando en condiciones maritimas peligrosas. Un riesgo alto de corrientes marinas regresara para temprano el domingo en la noche para la mayoria de las playas orientadas hacia el norte y este. .Comunicado sobre informacion reportada por observadores... No se espera activacion amplia de observadores. Favor de reportar cualquier informacion sobre inundaciones, vientos, oleaje y corrientes marinas al Servicio Nacional de Meteorologia en San Juan mientras siguen las indicaciones de las autoridades locales y estatales. AMZ715-725-VIZ001-002-030800- San Tomas, San John e Islas Adyacentes- Santa Cruz-Aguas cercanas del Atlantico y aguas costeras adyacentes del Caribe- 400 AM AST sabado 2 de octubre de 2021 Esta perspectiva sobre las condiciones peligrosas del tiempo es para Islas Virgenes Estadounidenses y las aguas costeras adyacentes. .Dia Uno...Hoy y esta noche .Tronadas...Existe el potencial de tronadas aisladas con lluvia fuerte y rafagas de vientos esta manana a traves de gran parte de las Islas Virgenes Americanas. .Inundaciones...Lluvias de moderadas a fuertes podrian resultar en acumulacion de agua en carreteras y areas de poco drenaje. .Vientos...Se esperan vientos sostenidos en exceso de 20 mph (17 nudos) a traves de sectores de las aguas mar afuera del Atlantico y Caribe, asi como los pasajes locales. .Oleaje...Se espera oleaje picado de hasta 6 pies a traves de sectores de las aguas mar afuera del Atlantico y Caribe, asi como los pasajes locales. .Corrientes marinas...Existe un riesgo moderado de corrientes marinas para todas las playas locales. .Calor...Se esperan indices de calor entre 102 y 107 grados, mayormente a traves de sectores de Santa Cruz. .Dias dos hasta el siete...domingo a viernes Se pronostica un aumento gradual de los vientos alisios para el domingo a temprano la proxima semana, resultando en condiciones maritimas peligrosas. Un riesgo alto de corrientes marinas regresara para temprano el domingo en la noche para la mayoria de las playas orientadas hacia el norte y este. .Comunicado sobre informacion reportada por observadores... No se espera activacion amplia de observadores. Favor de reportar cualquier informacion sobre inundaciones, vientos, oleaje y corrientes marinas al Servicio Nacional de Meteorologia en San Juan mientras siguen las indicaciones de las autoridades locales y estatales.
The San Juan radar (TJUA), 94 km away, was scanning. The volume nearest the first event began at 18:31 UTC.
1 thunderstorm wind, 1 flash flood. Local standard time, as filed.
Emergency management reported various sectors with fallen including Road PR-4491 and 485.
Emergency manager informed that Calle Esperanza was impassable.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Puerto Rico in 2021Every state in 2021This day in weather historyWarnings in Puerto Rico, October 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 986654, 986664.