A cold front moved over the area. This cold front along with abundant low to mid-level moisture and a trough aloft resulted areas of heavy rainfall activity across the north-central and northeastern portions of Puerto Rico during this period.
Every event with a place to put it. Tap one for its entry below.
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 cold front moved over the area. This cold front along with abundant low to mid-level moisture and a trough aloft resulted areas of heavy rainfall activity across the north-central and northeastern portions of Puerto Rico during this period.
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 Mar 9, 4:41 PM AST, 2 hours 9 minutes earlier.
Area Forecast Discussion
National Weather Service San Juan PR
441 PM AST Mon Mar 9 2020
.SYNOPSIS...A frontal boundary and associated plume of moisture
will enhance shower activity through Tuesday morning. Thereafter,
the chance for widespread showers will diminish, but patches of
low- level moisture and favorable conditions aloft due to an
approaching mid- to- upper level trough will support afternoon
deep convection through most of the workweek. Hazardous marine and
coastal conditions will continue during the next several days.
&&
.SHORT TERM...Tonight through Wednesday...
A wet weather pattern is expected to hold through at least Tuesday
morning. This is the result of a frontal boundary, that although
it is expected to remain over and to the north of the islands, the
associated plume of moisture will enhance cloudiness and shower
activity. As the boundary meanders away and weakens, the chance
for widespread shower activity is expected to decrease by
Tuesday. However, patches of low-level moisture, some remnants of
the frontal boundary and some the result of easterly disturbances
in the trade winds, will bring overnight and early morning shower
activity across the waters into portions of eastern Puerto Rico
and the US Virgin Islands. Nevertheless, lingering moisture
combined with local effects, diurnal heating, and favorable
conditions aloft due to an approaching mid to upper level trough,
will support the development of afternoon deep convection along
the interior and western sectors of Puerto Rico. Deep convection
can also be expected downwind from El Yunque into the Great San
Juan Metropolitan area, and downwind from the local islands into
portions of eastern Puerto Rico. There is a slight chance for
isolated thunderstorms, and a potential for urban and small stream
flooding with this activity.
A fresh to strong east to northeast flow will continue through
tonight. By Tuesday and Wednesday, winds are expected to slightly
diminish and favor a more east-southeast direction as a strong
surface high pressure continues to move eastward and away across
the central north Atlantic. Warmer temperatures should return to
northern Puerto Rico Tuesday and Wednesday under this flow.
.LONG TERM...Thursday through Tuesday...
.FROM PREV DISCUSSION... /issued 508 AM AST Mon Mar 9 2020/
The remnants of the cold front will continue to bring patches of
clouds and showers on Thursday and Friday. As the surface high
pressure system moves to the east, across the eastern Atlantic,
winds are expected to shift from the east to east-southeast.
Therefore, areas of eastern and southeastern Puerto Rico, as well as
the U.S. Virgin Islands should receive showers, especially during
the nighttime and in the early morning hours. In the afternoon, as
is usual with this weather pattern, showers should develop across
the northwestern quadrant of Puerto Rico due to a combination of the
available moisture and local effects. In addition, a trough in the
mid to upper levels will provide some instability across the region,
which could favor isolated thunderstorms with the strongest
activity on Thursday.
For Saturday, the latest guidance suggest drier air filtering in at
the mid-levels as the winds shift more from the northeast. However,
at the surface, enough moisture at the lower levels should, once
again, bring fragmented groups of clouds across the area. By Sunday
and into the beginning of the workweek, a ridge in the mid and upper
levels will build over the region with a drier air mass also
taking place over the area, limiting shower activity across the
islands.
&&
.AVIATION...TEMPO MVFR cigs expected across all the PR terminals
through the late evening hours due to SHRA associated to a frontal
boundary. Northeast winds 15-25 kt with possible gusts up to 35 kt
will continue through at least 23z. Conditions will gradually
improve overnight into Tuesday morning and winds are forecast to
decrease between 10-15 knots and more from the east late tonight.
Mainly VFR conditions expected across the USVI/Leeward terminals.
However, SHRA will move at times across TIST during the next 6-12
hours and this may cause tempo MVFR cigs.
&&
.MARINE...Hazardous marine conditions will continue across the
local waters due to increasing winds, a northerly swell and an
approaching frontal boundary. Seas up to 14 feet with occasional
seas up to 18 feet are expected across the Atlantic waters and
local passages, while lower seas up to 12 feet are expected
elsewhere. Therefore, Small Craft Advisories continue in effect.
Across coastal areas, there is a High Surf Advisory for beaches
along the north coast of Puerto Rico, Culebra and the northern US
Virgin Islands. In addition, there is a High Risk of Rip Currents
for most of the local beaches, except for beaches along the south
to southeast coast of Puerto Rico.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 73 85 72 84 / 90 40 60 60
STT 73 84 74 84 / 80 20 20 60
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...High Rip Current Risk through Wednesday afternoon for Culebra-
Mayaguez and Vicinity-North Central-Northeast-Northwest-San
Juan and Vicinity-Southwest.
High Surf Advisory until 6 AM AST Wednesday for Mayaguez and
Vicinity-North Central-Northeast-Northwest-San Juan and
Vicinity-Southeast.
High Rip Current Risk through Wednesday afternoon for Southeast-
Vieques.
High Surf Advisory until 6 AM AST Wednesday for Culebra.
VI...High Rip Current Risk through Wednesday afternoon for
St.Thomas...St. John...and Adjacent Islands.
High Rip Current Risk through Wednesday afternoon for St Croix.
High Surf Advisory until 6 AM AST Wednesday for St.Thomas...St.
John...and Adjacent Islands.
AM...Small Craft Advisory until 2 AM AST Wednesday for Coastal Waters
OF Southwestern Puerto Rico out 10 NM-Coastal Waters of
Southern Puerto Rico out 10 NM.
Small Craft Advisory until 2 PM AST Thursday for Caribbean
Waters of Puerto Rico from 10 NM to 17N-Coastal Waters of
Northern USVI and Culebra out 10 NM.
Small Craft Advisory until 8 PM AST Thursday for Anegada Passage
Southward to 17N-Atlantic Waters of Puerto Rico and USVI
from 10 NM to 19.5N-Coastal Waters of Northern Puerto Rico
out 10 NM-Mona Passage Southward to 17N.
Small Craft Advisory until 2 AM AST Thursday for Coastal Waters
OF Northwestern Puerto Rico out 10 NM-Coastal Waters of
Southern USVI Vieques and Eastern Puerto Rico out 10 NM.
&&
SHORT TERM...JA
LONG TERM....ICP
PUBLIC DESK...GLPerspectivas sobre Condiciones Peligrosas del Tiempo Servicio Nacional de Meteorologia San Juan PR 518 AM AST lunes 9 de marzo de 2020 AMZ710>745-PRZ001>013-100930- San Juan y Vecindad-Noreste-Sureste- Este Interior-Norte Central-Interior Central-Ponce y Vecindad- Noroeste-Oeste Interior-Mayaguez y Vecindad-Suroeste-Culebra-Vieques- Aguas cercanas y mar afuera del Atlantico y Caribe- 518 AM AST lunes 9 de marzo de 2020 Esta perspectiva sobre las condiciones peligrosas del tiempo es para Puerto Rico y las aguas costeras del Atlantico. .Dia Uno...Hoy y esta noche .Tronadas...Existe riesgo leve de tronadas con lluvia fuerte y vientos en rafaga breves esta tarde a traves de Puerto Rico, mayormente en el oeste e interior. .Inundaciones...Lluvias persistentes de moderadas a fuertes pudieran resultar en inundaciones urbanas y de riachuelos en areas, menos en el sur y sureste de Puerto Rico. .Vientos...Se esperan vientos sostenidos cerca de 20 mph (17 nudos) a traves de la mayoria del norte de Puerto Rico con rafagas de hasta 40 mph (35 nudos) probables a lo largo de la costa norte y las aguas del Atlantico. .Oleaje...Se espera oleaje peligroso de hasta 14 pies a traves de las aguas del Atlantico y sectores del norte de los pasajes del Caribe. Advertencias de resacas fuertes estan en efecto para la mayoria de la costa norte. .Corrientes marinas...Existe riesgo alto de corrientes marinas para las playas de Culebra y el norte de Puerto Rico y para Vieques. Se espera riesgo moderado en el resto del area. .Dias dos hasta el siete...martes a domingo El viento disminuira el miercoles seguido de oleaje peligroso y corrientes marinas. .Comunicado sobre informacion reportada por observadores... No se anticipa activacion amplia de observadores. Sin embargo, se les exhorta a los observadores individuales a reportar inundaciones y corrientes marinas al Servicio Nacional de Meteorologia en San Juan. AMZ715-725-VIZ001-002-100930- San Tomas, San John y Islas Adyacentes- Santa Cruz-Aguas cercanas del Atlantico y aguas costeras adyacentes del Caribe- 518 AM AST lunes 9 de marzo de 2020 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 riesgo leve de tronadas con lluvia fuerte y vientos en rafaga breves para esta tarde en San Thomas y San John. .Inundaciones...Lluvia localmente fuerte pudiera resultard en acumulacion de agua en carreteras con pobre drenaje. .Vientos...Se esperan vientos sostenidos cerca de 20 mph (17 nudos) a traves de la mayoria del norte de San Thomas y San John y las aguas cercanas del Atlantico y el Caribe. Rafagas de hasta 30 mph (26 nudos) son posibles. .Oleaje...Se espera oleaje peligroso de hasta 14 pies a traves de las aguas del Atlantico y sectores del norte de los pasajes del Caribe. Advertencias de resacas fuertes estan en efecto para la mayoria de la costa norte de San Thomas para esta noche. .Corrientes marinas...Existe un riesgo alto de corrientes marinas para las playas de San Thomas y las playas del norte de San John para hoy. .Dias dos hasta el siete...martes a domingo El viento disminuira el miercoles seguido de oleaje peligroso y corrientes marinas. .Comunicado sobre informacion reportada por observadores... No se anticipa activacion amplia de observadores. Sin embargo, se les exhorta a los observadores individuales a reportar inundaciones y corrientes marinas al Servicio Nacional de Meteorologia en San Juan.
The San Juan radar (TJUA), 43 km away, was scanning. The volume nearest the first event began at 22:50 UTC.
3 flash flood, 1 heavy rain, 1 debris flow. Local standard time, as filed.
Seven people were trapped in Rio Charco Azul due to a water surge.
Mudslide reported along Road PR-956 KM 6.1.
Road PR-962 between KM 0.6 and KM 0.8 was flooded with 8 feet of water.
The intersection of Road PR-3 and Road PR-185 was flooded.
Several streets in the Urbanization of Ciudad Jardin were flooded with 2 feet of water.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Puerto Rico in 2020Every state in 2020This day in weather historyWarnings in Puerto Rico, March 2020
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: 877668, 877669, 877670, 877671, 877672.