Alert archive / Connecticut / Mesoscale Discussions in 2012

Mesoscale Discussion 1496

July 18, 20126 counties in Massachusetts; 5 counties in New York; 5 counties in Rhode Island

The Storm Prediction Center issued this mesoscale discussion at Jul 18, 2012, 4:50 PM EDT for 6 counties in Massachusetts; 5 counties in New York; 5 counties in Rhode Island. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Jul 18, 2012, 4:50 PM EDT (20:50 UTC)
Expired: Jul 18, 2012, 6:15 PM EDT
In force: 85 min
Issued by: the Storm Prediction Center

Counties Bristol County, MA, Dukes County, MA, Hampden County, MA, Norfolk County, MA, Plymouth County, MA, Suffolk County, MA, Dutchess County, NY, Nassau County, NY, Putnam County, NY, Suffolk County, NY, Westchester County, NY, Bristol County, RI, Kent County, RI, Newport County, RI, Providence County, RI, Washington County, RI

The radar

The Brookhaven radar (KOKX), 90 km from the middle of the area, began a volume at 20:52 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 12:00Z, 8.8 hours before the alert went out and 90 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: 2129 J/kg
Mixed-layer CIN: -147 J/kg
Mixed-layer LCL: 1491 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 82 m²/s²
0-3 km storm-relative helicity: 95 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 10:25 AM EDT	Mesoscale Discussion	SPC		2 hr
Jul 18, 12:20 PM EDT	Severe Thunderstorm Watch	SPC	Greater Bridgeport Planning Region, Capitol Planning Region, Northwest Hills Planning Region, Lower Connecticut River Valley Planning Region, Naugatuck Valley Planning Region, Southeastern Connecticut Planning Region and 1 more	9 hr
Jul 18, 2:46 PM EDT	Mesoscale Discussion	SPC		89 min
Jul 18, 12:41 PM EDT	Severe Thunderstorm Watch	SPC	Sullivan	8 hr

Nearby

Mesoscale Discussions in Connecticut, 2012 Mesoscale Discussions in Massachusetts, 2012 Mesoscale Discussions in New York, 2012 Every mesoscale discussion in 2012

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.