Alert archive / Hawaii / Flash Flood Warnings in 2021
Flash Flood Warning 2, NWS Honolulu, HI
NWS Honolulu, HI issued this flash flood warning at Jan 18, 2021, 2:25 PM HST for Kalawao County, Hawaii. It was in force for 9 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
- Jan 18, 2021, 2:25 PM HST (00:25 UTC)
- Expired
- Jan 18, 2021, 11:15 PM HST
- In force
- 9 hr
- Issued by
- NWS Honolulu, HI
- Area
- Storm-based polygon
- Flood severity
- None
County Kalawao County, HI
The radar
The Molokai radar (PHMO), 15 km from the middle of the area, began a volume at 00:25 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.
The nearest sounding before it
Lihue, (PHLI), launched 00:00Z, 0.4 hours before the alert went out and 257 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 13 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 970 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- -63 m²/s²
- 0-3 km storm-relative helicity
- 102 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
811
WGHW50 PHFO 190025
FFWHFO
HIC009-190315-
/O.NEW.PHFO.FF.W.0002.210119T0025Z-210119T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
225 PM HST Mon Jan 18 2021
The National Weather Service in Honolulu has issued a
* Flash Flood Warning for...
The island of Molokai in Maui County
* Until 515 PM HST.
* At 225 PM HST, radar indicated intense downpours from near
Hoolehua, across the northern portion of Molokai, to near Halawa
Valley. Rain was falling at a rate of 2 to 4 inches per hour. This
is in an area which already was affected by heavy rainfall last
night. Flash flooding is occurring or expected to begin shortly.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar indicated.
IMPACT...Flooding in drainages, streams, rivers, roads,
properties, and other low-lying areas. Public road
closures possible in some areas. Landslides are
possible in steep terrain.
* This warning includes the entire island of Molokai.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Do not cross fast flowing or rising water in your vehicle, or on
foot. Turn around, don't drown.
The heavy rains may cause rock and mudslides in steep terrain areas.
&&
This warning may need to be extended beyond 515 PM HST if flooding
persists.
This Flash Flood Warning replaces the previously issued Flood
Advisory that was in effect for The island of Molokai in Maui County.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
FLASH FLOOD...RADAR INDICATED
$$
R BALLARD5 follow-up statements
823
WGHW70 PHFO 190212
FFSHFO
Flash Flood Statement
National Weather Service Honolulu HI
412 PM HST Mon Jan 18 2021
HIC009-190315-
/O.CON.PHFO.FF.W.0002.000000T0000Z-210119T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
412 PM HST Mon Jan 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 515 PM HST THIS
AFTERNOON FOR THE ISLAND OF MOLOKAI IN MAUI COUNTY...
At 412 PM HST, stream gauges at Kaunakakai Gulch and Kawela Gulch
were showing very high water levels, indicating flash flooding is
likely ongoing near these and other drainages. Although radar
indicates that the heavy rainfall has diminished a bit over east
Molokai, there were still heavy showers falling over the mountains,
in areas which are already saturated from recent heavy rains.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Stream Gauges.
IMPACT...Flooding in drainages, streams, rivers, roads,
properties, and other low-lying areas. Public road
closures possible in some areas. Landslides are possible
in steep terrain.
Some locations that could experience flash flooding include...
Kualapuu, Kaunakakai, Hoolehua, Kalaupapa National Park, Kawela,
Kamalo, Maunaloa, Ualapue, Pukoo, Kepuhi, Halawa Valley and
Molokai Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay away from streams, rivers, drainage ditches, and culverts.
NEVER drive into areas where water covers the road!
Do not cross fast flowing or rising water in your vehicle, or on
foot. Turn around, don't drown.
The heavy rains may cause rock and mudslides in steep terrain areas.
&&
This warning may need to be extended beyond 515 PM HST if flooding
persists.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
FLASH FLOOD...GAUGE INDICATED
$$
R BALLARD720
WGHW50 PHFO 190312
FFWHFO
HIC009-190615-
/O.EXT.PHFO.FF.W.0002.000000T0000Z-210119T0615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
512 PM HST Mon Jan 18 2021
The National Weather Service in Honolulu has extended the
* Flash Flood Warning for...
The island of Molokai in Maui County in Hawaii...
* Until 815 PM HST.
* At 512 PM HST, stream gauges on Molokai continued to report high
stream levels on Molokai. Law enforcement reported Kamehameha V
highway was closed at Pukoo and Kamalo. Although the rain has
subsided somewhat, light to moderate rain continues to fall over
areas saturated by earlier intense rainfall.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar indicated.
IMPACT...Flooding in drainages, streams, rivers, roads,
properties, and other low-lying areas. Public road
closures possible in some areas. Landslides are
possible in steep terrain.
* This warning includes the entire island of Molokai.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay away from streams, rivers, drainage ditches, and culverts, even
if they are currently dry.
Do not cross fast flowing or rising water in your vehicle, or on
foot. Turn around, don't drown!
The heavy rains may cause rock and mudslides in steep terrain areas.
&&
This warning may need to be extended beyond 815 PM HST if flooding
persists.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
FLASH FLOOD...RADAR INDICATED
$$
R BALLARD694
WGHW50 PHFO 190610
FFWHFO
HIC009-190915-
/O.EXT.PHFO.FF.W.0002.000000T0000Z-210119T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Honolulu HI
810 PM HST Mon Jan 18 2021
The National Weather Service in Honolulu has extended the
* Flash Flood Warning for...
The island of Molokai in Maui County in Hawaii...
* Until 1115 PM HST.
* At 810 PM HST, radar indicated moderate to heavy rain over east
Molokai, in areas that have already received a significant amount
of rainfall earlier today. Although stream levels have fallen
slightly over the past couple hours, rainfall intensity is now
increasing over these same areas which received the earlier heavy
rains. Rainfall rates of around 1 inch per hour are now occurring,
and this will likely lead to additional high water levels on area
streams along with flash flooding of low lying and poor drainage
areas.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar indicated.
IMPACT...Flooding in drainages, streams, rivers, roads,
properties, and other low-lying areas. Public road
closures possible in some areas. Landslides are
possible in steep terrain.
* Some locations that will experience flash flooding include...
Kualapuu, Kaunakakai, Hoolehua, Kalaupapa National Park, Kawela,
Kamalo, Maunaloa, Ualapue, Pukoo, Kepuhi, Halawa Valley and
Molokai Airport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay away from streams, rivers, drainage ditches, and culverts, even
if they are currently dry.
Do not cross fast flowing or rising water in your vehicle, or on
foot. Turn around, don't drown.
The heavy rains may cause rock and mudslides in steep terrain areas.
&&
This warning may need to be extended beyond 1115 PM HST if flooding
persists.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
FLASH FLOOD...RADAR INDICATED
$$
JELSEMA010
WGHW70 PHFO 190756
FFSHFO
Flash Flood Statement
National Weather Service Honolulu HI
956 PM HST Mon Jan 18 2021
HIC009-190915-
/O.CON.PHFO.FF.W.0002.000000T0000Z-210119T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
956 PM HST Mon Jan 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1115 PM HST THIS
EVENING FOR THE ISLAND OF MOLOKAI IN MAUI COUNTY...
At 956 PM HST, radar indicated moderate to heavy rain continues to
fall over east Molokai, with rainfall rates of around 1 inch per
hour. Area streams are once again on the rise due to the additional
rainfall over already saturated grounds, with the Kawela Gulch now
reaching levels that have produced closures of Kamehameha Highway
in the past, including low water crossings such as the Kamalo Dip
between mile markers 10 and 11. Moderate to heavy rainfall is
expected to continue over east Molokai for at least the next hour or
two, and this will likely continue to produce flooding of low lying
and poor drainage areas.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar indicated.
IMPACT...Flooding in drainages, streams, rivers, roads,
properties, and other low-lying areas. Public road
closures possible in some areas. Landslides are possible
in steep terrain.
Some locations that will experience flash flooding include...
The entire island of Molokai.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Stay away from streams, rivers, drainage ditches, and culverts, even
if they are currently dry.
Do not cross fast flowing or rising water in your vehicle, or on
foot. Turn around, don't drown.
The heavy rains may cause rock and landslides in steep terrain areas.
&&
This warning may need to be extended beyond 1115 PM HST if flooding
persists.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
FLASH FLOOD...RADAR INDICATED
$$
JELSEMA316
WGHW70 PHFO 190911
FFSHFO
Flash Flood Statement
National Weather Service Honolulu HI
1111 PM HST Mon Jan 18 2021
HIC009-190921-
/O.EXP.PHFO.FF.W.0002.000000T0000Z-210119T0915Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Maui HI-
1111 PM HST Mon Jan 18 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 1115 PM HST THIS EVENING FOR
THE ISLAND OF MOLOKAI IN MAUI COUNTY...
The heavy rain has ended and flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures. Stream
levels remain elevated and will likely remain elevated for the next
several hours due to the recent heavy rains. If additional heavy rain
develops later tonight, stream levels will likely rapidly rise due
to the already saturated grounds, and if this occurs, a Flood
Advisory or Flash Flood Warning may be required.
A Flash Flood Watch remains in effect until 600 PM HST Tuesday for
Molokai.
LAT...LON 2119 15728 2124 15728 2125 15726 2121 15701
2124 15697 2120 15693 2120 15677 2117 15669
2115 15669 2105 15680 2103 15687 2109 15709
2106 15725 2110 15734
$$
JELSEMAThe office that day
Everything else NWS Honolulu, HI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 18, 2:59 PM HST | Flash Flood Warning | HFO | Kalawao | 3 hr |
| Jan 18, 3:41 PM HST | Areal Flood Advisory | HFO | Hawaii | 3 hr |
| Jan 18, 5:54 PM HST | Areal Flood Advisory | HFO | Kalawao | 5 hr |
| Jan 19, 5:38 AM HST | Areal Flood Advisory | HFO | Honolulu | 3 hr |
| Jan 19, 10:26 AM HST | Special Marine Warning | HFO | 2 hr | |
| Jan 19, 10:55 AM HST | Areal Flood Advisory | HFO | Kauai | 2 hr |
| Jan 19, 12:01 PM HST | Special Marine Warning | HFO | 78 min | |
| Jan 19, 1:18 PM HST | Flash Flood Warning | HFO | Kauai | 9 hr |
Nearby
Flash Flood Warnings in Hawaii, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.