Alert archive / New York / Flash Flood Warnings in 1990

Flash Flood Warning 11, NWS New York, NY

August 11, 1990Rockland County, New York

NWS New York, NY issued this flash flood warning at Aug 11, 1990, 8:00 PM EDT for Rockland County, New York. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued: Aug 11, 1990, 8:00 PM EDT (00:00 UTC)
Expired: Aug 11, 1990, 10:00 PM EDT
In force: 2 hr
Issued by: NWS New York, NY
Area: Whole counties

County Rockland County, NY

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Albany, NY (KALB), launched 00:00Z, 0.0 hours before the alert went out and 172 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1310 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 1044 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: -0.1
Supercell composite: -0.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KNYC 120017
FFWNYC
NYC087-120215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED
URBAN AND SMALL STREAM FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
800 PM EDT SAT AUG 11 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A URBAN AND SMALL
STREAM FLOOD WARNING EFFECTIVE UNTIL 1000 PM EDT FOR PEOPLE IN
THE FOLLOWING COUNTY

   IN THE STATE OF NEW YORK
      EASTERN ROCKLAND

<
HEAVY RAINS OVER THE EASTERN PART OF ROCKLAND COUNTY IN THE PAST
COUPLE OF HOURS HAVE SENT THE HACKENSACK RIVER IN NYACK OVER ITS
BANKS. SOME SURROUNDING ROADS ARE IMPASSABLE DUE TO HIGH WATER.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE ROADWAY.
THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY.
VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED IMMEDIATELY.
MOVE TO HIGHER GROUND.

 EY

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Aug 11, 6:37 PM EDT, 1 hour 23 minutes before

NJZ001-005-007-015-NYZ014>017-110100
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW YORK CITY NY
630 PM EDT SAT AUG 11 1990

...MORE HEAVY SHOWERS AND THUNDERSTORMS OVER INLAND AREAS...

SCATTERED SHOWERS AND THUNDERSTORMS WHICH DEVELOPED DURING THE MID
AFTERNOON HOURS OVER NORTHERN NEW JERSEY AND OVER ROCKLAND AND
WESTCHESTER COUNTIES HAVE PERSISTED OVER THESE AREAS. LOCALIZED
HEAVY DOWNPOURS ACCOMPANYING THESE SHOWERS MAY DUMP ANOTHER INCH
OR TWO OF RAIN OVER ALREADY SATURATED GROUND BEFORE TAPERING OFF
AND ENDING BEFORE MIDNIGHT.

A FLOOD WATCH REMAINS IN EFFECT UNTIL 9 PM FOR NORTHERN NEW JERSEY
AND SOUTHEASTERN NEW YORK...EXCEPT LONG ISLAND.

RIVER AND STREAM LEVELS REMAIN HIGH...AND PROLONGED HEAVY RAINS
IN VULNERABLE AREAS WILL CAUSE SUSCEPTIBLE RIVERS AND STREAMS TO
ONCE AGAIN GO OVER THEIR BANKS.
<
EY

Nearby

Flash Flood Warnings in New York, 1990 Every flash flood warning in 1990

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.