Alert archive / Guam / Flash Flood Warnings in 2021

Flash Flood Warning 7, NWS Guam

September 23, 2021

NWS Guam issued this flash flood warning at Sep 23, 2021, 8:28 PM CDT. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Sep 23, 2021, 8:28 PM CDT (01:28 UTC)
Expired: Sep 23, 2021, 10:53 PM CDT
In force: 2 hr
Issued by: NWS Guam
Area: Storm-based polygon
Flood severity: None

The text

As transmitted.

205 
WGMY50 PGUM 240128
FFWGUM
GUC010-240430-
/O.NEW.PGUM.FF.W.0007.210924T0128Z-210924T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tiyan GU
1128 AM ChST Fri Sep 24 2021

The National Weather Service in Tiyan has issued a

* Flash Flood Warning for...
  Guam Island in the Marianas...

* Until 230 PM ChST.

* At 1128 AM ChST, Automated rain gauges indicated heavy rain 
  falling across the warned area. Between 2 and 4 inches of rain 
  have fallen. The expected rainfall rate is 0.5 to 1 inch in 3 
  hours. Additional rainfall amounts of 1 to 3 inches are possible 
  in the warned area. Flash flooding is already occurring.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

In hilly terrain there are low water crossings which are potentially 
dangerous in heavy rain. Do not attempt to cross flooded roads. Find 
an alternate route.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 1341 14464 1340 14466 1344 14462 1342 14467
      1345 14466 1346 14469 1346 14463 1348 14477
      1365 14486 1360 14490 1360 14495 1352 14492
      1342 14478 1327 14475 1323 14464

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...0.5-1 INCH IN 3 HOURS

$$

1 follow-up statement

315 
WGMY70 PGUM 240353
FFSGUM

Flash Flood Statement
National Weather Service Tiyan GU
153 PM ChST Fri Sep 24 2021

GUC010-240403-
/O.CAN.PGUM.FF.W.0007.000000T0000Z-210924T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Guam GU-
153 PM ChST Fri Sep 24 2021

...FLASH FLOOD WARNING IS CANCELLED FOR GUAM...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat.

A Flood Watch remains in effect until 600 AM ChST Saturday for a 
portion of the Marianas.

LAT...LON 1341 14464 1340 14466 1344 14462 1342 14467
      1345 14466 1346 14469 1346 14463 1348 14477
      1365 14486 1360 14490 1360 14495 1352 14492
      1342 14478 1327 14475 1323 14464

$$

The office that day

Everything else NWS Guam issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 24, 11:43 AM CDT	Areal Flood Advisory	GUM		2 hr

Nearby

Flash Flood Warnings in Guam, 2021 Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.