Alert archive / New York / Flash Flood Warnings in 2017

Flash Flood Warning 21, NWS New York, NY

October 24, 2017Suffolk County, New York

NWS New York, NY issued this flash flood warning at Oct 24, 2017, 11:12 PM EDT for Suffolk County, New York. It was in force for 63 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Oct 24, 2017, 11:12 PM EDT (03:12 UTC)
Expired
Oct 25, 2017, 12:15 AM EDT
In force
63 min
Issued by
NWS New York, NY
Area
Storm-based polygon
Flood severity
None

County Suffolk County, NY

The radar

The Brookhaven radar (KOKX), 35 km from the middle of the area, began a volume at 03:17 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

Brookhaven, NY (KOKX), launched 00:00Z, 3.2 hours before the alert went out and 35 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.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2017-10-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 473 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2017-10-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 248 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
473 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
604 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
248 m²/s²
0-3 km storm-relative helicity
290 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.3

Open this sounding in Storm Lab

The text

As transmitted.

619 
WGUS51 KOKX 250312
FFWOKX
NYC103-250415-
/O.NEW.KOKX.FF.W.0021.171025T0312Z-171025T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
1112 PM EDT TUE OCT 24 2017

The National Weather Service in Upton NY has issued a

* Flash Flood Warning for...
  Western Suffolk County in southeastern New York...

* Until 1215 AM EDT

* At 1112 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Up to three inches of rain have
  already fallen. 

* Some locations that will experience flooding include...
  Islip, Deer Park, Lindenhurst, Babylon, Dix Hills, Bay Shore,
  Sayville, Captree State Park, Gilgo State Park, Davis Park, West
  Islip, Copiague, North Bay Shore, Kings Park and East Islip.

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

&&

LAT...LON 4060 7343 4086 7333 4087 7333 4074 7325
      4073 7318 4076 7315 4088 7322 4091 7332
      4088 7333 4094 7332 4094 7329 4093 7318
      4080 7317 4073 7303 4065 7337 4065 7320
      4069 7298 4060 7342

$$

MALOIT
1 follow-up statement
831 
WGUS71 KOKX 250317
FFSOKX

Flash Flood Statement
National Weather Service New York NY
1117 PM EDT TUE OCT 24 2017

NYC103-250327-
/O.CAN.KOKX.FF.W.0021.000000T0000Z-171025T0415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Suffolk NY-
1117 PM EDT TUE OCT 24 2017

...THE FLASH FLOOD WARNING FOR WESTERN SUFFOLK COUNTY IS CANCELLED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 4060 7343 4086 7333 4087 7333 4074 7325
      4073 7318 4076 7315 4088 7322 4091 7332
      4088 7333 4094 7332 4094 7329 4093 7318
      4080 7317 4073 7303 4065 7337 4065 7320
      4069 7298 4060 7342

$$

MALOIT

The office that day

Everything else NWS New York, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 24, 10:43 PM EDTFlash Flood WatchOKXSuffolk6 hr
Oct 25, 1:59 AM EDTSmall Craft AdvisoryOKX62 hr

Nearby

Flash Flood Warnings in New York, 2017Every flash flood warning in 2017

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.