Alert archive / New York / Flash Flood Warnings in 2021
Flash Flood Warning 15, NWS New York, NY
NWS New York, NY issued this flash flood warning at Jul 9, 2021, 9:44 AM EDT for Suffolk County, New York. It was in force for 2 hr. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 9, 2021, 9:44 AM EDT (13:44 UTC)
- Expired
- Jul 9, 2021, 11:52 AM EDT
- In force
- 2 hr
- Issued by
- NWS New York, NY
- Area
- Storm-based polygon
- Flood severity
- None
County Suffolk County, NY
The radar
The Brookhaven radar (KOKX), 33 km from the middle of the area, began a volume at 13:46 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 9, 11:00 AM EDT | FLASH FLOOD | 1 S Centerport, NY | SEVERAL STREETS ARE IMPASSABLE DUE TO FLOODING. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Albany, NY (KALY), launched 12:00Z, 1.7 hours before the alert went out and 201 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
- 3 J/kg
- Mixed-layer CIN
- -156 J/kg
- Mixed-layer LCL
- 764 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 67 m²/s²
- 0-3 km storm-relative helicity
- 88 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
730
WGUS51 KOKX 091344
FFWOKX
NYC103-091645-
/O.NEW.KOKX.FF.W.0015.210709T1344Z-210709T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
944 AM EDT Fri Jul 9 2021
The National Weather Service in Upton has issued a
* Flash Flood Warning for...
West Central Suffolk County in southeastern New York...
* Until 1245 PM EDT.
* At 944 AM EDT, Doppler radar indicated heavy rain across the
warned area. Between 1.5 and 3 inches of rain have fallen. The
expected rainfall rate is 1 to 1.5 inches in 1 hour. Flash
flooding is ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Brentwood, Commack, Huntington Station, Centereach, Deer Park,
Medford, Hauppauge, Ronkonkoma, Huntington, Stony Brook, Port
Jefferson, Northport, Coram, Dix Hills, Smithtown, Farmingville,
Mount Sinai, Centerport, Central Islip and East Northport.
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.
Excessive runoff from heavy rainfall will cause flooding of urban
areas, highways, streets and underpasses as well as other drainage
areas and low lying spots.
&&
LAT...LON 4094 7343 4094 7342 4096 7341 4097 7340
4094 7334 4095 7329 4092 7322 4093 7317
4097 7318 4099 7312 4098 7306 4098 7295
4083 7296 4072 7339
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-1.5 INCHES IN 1 HOUR
$$
JM2 follow-up statements
626
WGUS71 KOKX 091507
FFSOKX
Flash Flood Statement
National Weather Service New York NY
1107 AM EDT Fri Jul 9 2021
NYC103-091645-
/O.CON.KOKX.FF.W.0015.000000T0000Z-210709T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Suffolk NY-
1107 AM EDT Fri Jul 9 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 PM EDT THIS
AFTERNOON FOR WEST CENTRAL SUFFOLK COUNTY...
At 1107 AM EDT, Doppler radar indicated moderate to heavy rain
across the warned area. Between 1 and 2.5 inches of rain have fallen
over the past 3 hours. The expected rainfall rate is 0.25 to 0.75
inches in 1 hour. This additional rainfall will exacerbate any
existing residual flooding. Please continue to heed remaining road
closures.
HAZARD...Flash flooding caused by heavy rain.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban areas,
highways, streets and underpasses as well as other poor
drainage and low-lying areas.
Some locations that will experience flash flooding include...
Brentwood, Commack, Huntington Station, Centereach, Deer Park,
Medford, Hauppauge, Ronkonkoma, Huntington, Stony Brook, Port
Jefferson, Northport, Coram, Dix Hills, Smithtown, Farmingville,
Mount Sinai, Centerport, Central Islip and East Northport.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
Excessive runoff from heavy rainfall will cause flooding of urban
areas, highways, streets and underpasses as well as other drainage
areas and low lying spots.
&&
LAT...LON 4094 7343 4094 7342 4096 7341 4097 7340
4094 7334 4095 7329 4092 7322 4093 7317
4097 7318 4099 7312 4098 7306 4098 7295
4083 7296 4072 7339
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.25-0.75 INCHES IN 1 HOUR
$$
JM894
WGUS71 KOKX 091552
FFSOKX
Flash Flood Statement
National Weather Service New York NY
1152 AM EDT Fri Jul 9 2021
NYC103-091602-
/O.CAN.KOKX.FF.W.0015.000000T0000Z-210709T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Suffolk NY-
1152 AM EDT Fri Jul 9 2021
...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL SUFFOLK
COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flash Flood Watch remains in effect until 1200 PM EDT for a
portion of southeast New York.
LAT...LON 4094 7343 4094 7342 4096 7341 4097 7340
4094 7334 4095 7329 4092 7322 4093 7317
4097 7318 4099 7312 4098 7306 4098 7295
4083 7296 4072 7339
$$
JMThe office that day
Everything else NWS New York, NY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 8, 8:17 PM EDT | Areal Flood Advisory | OKX | Bronx, New York, Westchester | 3 hr |
| Jul 9, 3:15 AM EDT | Areal Flood Advisory | OKX | New York | 3 hr |
| Jul 9, 4:36 AM EDT | Special Marine Warning | OKX | 84 min | |
| Jul 9, 5:30 AM EDT | Areal Flood Advisory | OKX | Bronx, Kings, Nassau, New York, Queens, Richmond and 3 more | 3 hr |
| Jul 9, 5:37 AM EDT | Special Marine Warning | OKX | 83 min | |
| Jul 9, 5:55 AM EDT | Special Marine Warning | OKX | 65 min | |
| Jul 9, 6:15 AM EDT | Special Marine Warning | OKX | 90 min | |
| Jul 9, 6:28 AM EDT | Special Marine Warning | OKX | 62 min | |
| Jul 9, 6:45 AM EDT | Areal Flood Advisory | OKX | Suffolk | 5 hr |
| Jul 9, 7:09 AM EDT | Areal Flood Advisory | OKX | Putnam, Westchester | 3 hr |
| Jul 9, 7:22 AM EDT | Special Marine Warning | OKX | 53 min | |
| Jul 9, 8:29 AM EDT | Areal Flood Advisory | OKX | Bronx, Kings, Nassau, New York, Queens, Richmond and 2 more | 61 min |
| Jul 9, 8:56 AM EDT | Flash Flood Warning | OKX | Nassau, Suffolk, Westchester | 3 hr |
| Jul 9, 10:22 AM EDT | Areal Flood Advisory | OKX | Putnam, Westchester | 2 hr |
| Jul 9, 11:39 AM EDT | Special Weather Statement | OKX | Suffolk | 111 min |
| Jul 9, 12:43 PM EDT | Flash Flood Watch | OKX | Suffolk | 77 min |
| Jul 9, 2:09 PM EDT | Small Craft Advisory | OKX | 24 hr | |
| Jul 9, 3:34 PM EDT | Rip Current Statement | OKX | Kings, Nassau, Queens, Suffolk | 29 hr |
Nearby
Flash Flood Warnings in New York, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.