Alert archive / Maryland / Flash Flood Warnings in 1990

Flash Flood Warning 7, NWS Baltimore/Washington

July 12, 1990Anne Arundel County, City of Baltimore, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jul 12, 1990, 7:37 PM EDT for Anne Arundel County, City of Baltimore, Maryland. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued: Jul 12, 1990, 7:37 PM EDT (23:37 UTC)
Expired: Jul 12, 1990, 9:45 PM EDT
In force: 2 hr
Issued by: NWS Baltimore/Washington
Area: Whole counties

Counties Anne Arundel County, MD, City of Baltimore, MD

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

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.6 hours before the alert went out and 73 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: 69 J/kg
Mixed-layer CIN: -180 J/kg
Mixed-layer LCL: 596 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 127 m²/s²
0-3 km storm-relative helicity: 150 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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, Jul 12, 5:00 PM EDT, 2 hours 37 minutes before

MDZ001>007-122100

NATIONAL WEATHER SERVICE BALTIMORE MD
SPECIAL WEATHER STATEMENT
500 PM EDT THU JUL 12 1990

 ...ALL OF CENTRAL AND EASTERN MARYLAND UNDER A SEVERE THUNDERSTORM
    WATCH UNTIL 10 PM EDT THIS EVENING...

WEATHER RADAR AT 4.45PM WAS INDICATING HEAVY THUNDERSTORMS OVER PORTIONS
OF NORTHERN VIRGINIA. THESE STORMS ARE MOVING NORTHEAST AT ABOUT 35 MPH.
THE MOST INTENSE STORMS ARE PRESENTING IN LOUDOUN AND PRINCE WILLIAM
COUNTIES IN NORTHERN VIRGINIA. QUARTER SIZE HAIL HAVE BEEN REPORTED WITH
THIS ACTIVITY.

THESE STORMS WILL BE CROSSING THE POTOMAC ENTERING SOUTH CENTRAL MARYLAND
WITHIN THE HOUR. OTHER STORMS NOT AS STRONG ARE DEVELOPING OVER CENTRAL
AND NORTHERN VIRGINIA AND IN MONTGOMERY AND FREDERICK COUNTIES.

THESE STORMS HAVE THE POTENTIAL FOR SEVERE WEATHER..AND THE PUBLIC IS URGED
TO KEEP ABREAST OF THE RAPIDLY CHANGING CONDITIONS AND TO SEEK SAFE SHELTER
IMMEDIATELY IF THREATHENING CONDITIONS APPROACH AND REPORST ANY SEVERE
WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY FOR RELAY TO THE NATIONAL
WEATHER SERVICE.

FIGUEROA

Special weather statement, Jul 12, 5:46 PM EDT, 1 hour 51 minutes before

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Special weather statement, Jul 12, 6:06 PM EDT, 1 hour 31 minutes before

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Special weather statement, Jul 12, 6:09 PM EDT, 1 hour 28 minutes before

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<head>
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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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      <p id="message2">
        Please try again in a few minutes.
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Special weather statement, Jul 12, 6:10 PM EDT, 1 hour 27 minutes before

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<head>
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  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 12, 5:54 PM EDT	Severe Thunderstorm Warning	LWX	Montgomery	66 min
Jul 12, 7:37 PM EDT	Flash Flood Warning	LWX	Baltimore, Cecil, Harford	2 hr
Jul 12, 7:37 PM EDT	Flash Flood Warning	LWX	Queen Anne's	2 hr
Jul 12, 4:39 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier, Loudoun, Prince William	66 min
Jul 12, 5:02 PM EDT	Tornado Warning	LWX	Fauquier	28 min
Jul 12, 5:35 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Loudoun	40 min
Jul 12, 5:54 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, City of Alexandria	66 min
Jul 12, 5:54 PM EDT	Severe Thunderstorm Warning	LWX	City of Falls Church	66 min
Jul 12, 5:54 PM EDT	Severe Thunderstorm Warning	LWX	City of Fairfax	66 min

Nearby

Flash Flood Warnings in Maryland, 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.