Flash Flood Warning 10, NWS Guam

Issued

Oct 6, 2021, 8:38 PM CDT (01:38 UTC)

Expired

Oct 6, 2021, 9:52 PM CDT

In force

74 min

Issued by

NWS Guam

Area

Storm-based polygon

Flood severity

None

The Andersen AFB radar (PGUA), 19 km from the middle of the area, began a volume at 01:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

239 
WGMY50 PGUM 070138
FFWGUM
GUC010-070300-
/O.NEW.PGUM.FF.W.0010.211007T0138Z-211007T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tiyan GU
1138 AM ChST Thu Oct 7 2021

The National Weather Service in Tiyan has issued a

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

* Until 100 PM ChST.

* At 1138 AM ChST, Doppler radar and automated rain gauges indicated 
  heavy showers and thunderstorms producing heavy downpours across 
  southern to central Guam. Between 0.5 and 1.5 inches of rain have 
  fallen with a rain rate of 1 to 2 inches per hour. Additional 
  rainfall amounts of 1 to 2 inches are possible for this area. 
  Flash flooding is imminent, especially for areas near steep 
  terrain.

  HAZARD...Flash flooding caused by training heavy showers and
           thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of streams, urban areas, streets, and
           other poor drainage and low-lying areas.

* Southern to central Guam

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.

Stay away or be swept away. River banks and culverts can become 
unstable and unsafe.

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

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Hikers should avoid streams or creeks.

&&

LAT...LON 1334 14463 1340 14466 1342 14464 1344 14480
      1339 14477 1334 14477 1333 14476 1332 14477
      1327 14475 1325 14472 1323 14465 1324 14464
      1324 14468 1325 14467 1333 14465

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

BPB/NRS/JLS

166 
WGMY70 PGUM 070252
FFSGUM

Flash Flood Statement
National Weather Service Tiyan GU
1252 PM ChST Thu Oct 7 2021

GUC010-070302-
/O.CAN.PGUM.FF.W.0010.000000T0000Z-211007T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Guam GU-
1252 PM ChST Thu Oct 7 2021

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

Although light rains continue across Guam, heavy showers have ended 
and are no longer expected in the next couple of hours. Urban and 
small stream flooding is no longer expected to pose a threat.

LAT...LON 1334 14463 1340 14466 1342 14464 1344 14480
      1339 14477 1334 14477 1333 14476 1332 14477
      1327 14475 1325 14472 1323 14465 1324 14464
      1324 14468 1325 14467 1333 14465

$$

WBA

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

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