Alert archive / Iowa / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 132, NWS Des Moines, IA

August 2, 2015Audubon County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Aug 2, 2015, 4:37 AM CDT for Audubon County, Iowa. It was in force for 41 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 2, 2015, 4:37 AM CDT (09:37 UTC)
Expired: Aug 2, 2015, 5:18 AM CDT
In force: 41 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Audubon County, IA

The radar

The Des Moines radar (KDMX), 98 km from the middle of the area, began a volume at 09:40 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

Davenport, (KDVN), launched 00:00Z, 9.6 hours before the alert went out and 366 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: 972 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 1560 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 80 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.5

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 2, 2:42 AM CDT, 1 hour 55 minutes earlier.

Area forecast discussion, Aug 2, 2:42 AM CDT, 1 hour 55 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
242 AM CDT SUN AUG 2 2015

.SHORT TERM /TODAY/...
ISSUED AT 242 AM CDT SUN AUG 2 2015

EARLY MORNING CONVECTION OVER SOUTHERN MN CONTINUES TO MOVE EAST
WHILE IRSAT SHOWING CLOUDS COOLING OVER NORTHERN IA IN RESPONSE TO
WEAK IMPULSE AND WARM AIR ADVECTION CROSSING THE AREA. A FEW SHOWERS
HAVE ATTEMPTED TO DEVELOP...BUT EARLIER SUBJECTIVE H850 ANALYSIS
SHOWING DRY AIR ALOFT OVER MOST OF IOWA HINTS AT ONLY MODEST
DEVELOPMENT THROUGH REMAINDER OF OVERNIGHT. WILL MONITOR AND UPDATE
IF NECESSARY. SAME STORY ACROSS EASTERN NEBRASKA...STORMS FIRING IN
MORE FAVORABLE MOISTURE PLUME AT 0715Z...BUT AS THEY PROGRESS TOWARD
WESTERN CWA BOUNDARY BY 12Z...SUSPECT THEY TOO WILL GENERALLY WEAKEN
WITH TIME. THERE HAS BEEN AN ISOLATED CELL NEAR CASS COUNTY OVER THE
PAST HOUR SO A FEW STORMS MAY YET DEVELOP OVER THE SOUTH PRIOR TO
12Z. MEANWHILE FOR THE REMAINDER OF THE DAY...THE MAIN SFC LOW OVER
CENTRAL MN WILL TRACK EAST TODAY DRAGGING A BOUNDARY ACROSS THE AREA
BY LATE AFTERNOON. AHEAD OF IT...NARROW RIBBON OF WARM H850 AIR WILL
MIX DURING THE AFTERNOON HOURS BRINGING HIGHS CLOSER TO 90 OVER THE
SOUTH HALF WITH A FEW URBAN AREAS LIKELY REACHING LOWER 90S BY LATE
AFTERNOON. MUCAPE RISES TO OVER 3000 J/KG ALONG THE BOUNDARY IN THE
AFTERNOON HOURS WHICH SHOULD SUPPORT THE MARGINAL THREAT FOR A SVR
STORM AS SCATTERED STORMS DEVELOP. H700 TEMPS BUILDING TO 10-11C BY
00Z WHICH MAY INHIBIT UNTIL 21-00Z. FOR NOW WILL EXPECT A DRY
MORNING/EARLY AFTERNOON WITH BEST POTENTIAL FOR THUNDERSTORMS LATE
AFTERNOON WHICH CORRESPONDS TO TIME OF INCREASING 0-6KM BULK SHEAR
TO 30-35KTS AS WELL NEAR THE BOUNDARY. SOUTHWEST WINDS DURING THE
DAY WILL MIX TO 15 TO 25 MPH...SO BREEZY AT TIMES WITH DEW POINTS
REMAINING IN THE UPPER 60S TO LOWER 70S. THIS WILL PUSH THE HEAT
INDEX TO 95 TO 98F ACROSS THE SOUTH TODAY.

.LONG TERM /TONIGHT THROUGH FRIDAY/...
ISSUED AT 242 AM CDT SUN AUG 2 2015

COLD FRONTAL BOUNDARY TO BE SITUATED ACROSS THE SOUTHERN PORTION OF
THE STATE BY EARLY EVENING...AND WILL CONTINUE TO PUSH SOUTH
OVERNIGHT. THEREFORE MAY SEE SOME STORMS ONGOING AT THE BEGINNING OF
THE PERIOD BEFORE ACTIVITY PUSHES SOUTH INTO MISSOURI BY LATE
EVENING. NAM TRIES TO HAVE FRONT STALL OUT ACROSS SRN IA...BUT SEEMS
TO BE THE OUTLIER WITH THE REMAINDER OF THE MODELS SHOVING IT
FURTHER SOUTH INTO MISSOURI AS AN AREA OF HIGH PRESSURE BUILDS INTO
THE STATE. THEREFORE HAVE MAINLY DRY CONDITIONS FOR LATE SUNDAY
NIGHT INTO MONDAY. MAY SEE THE FRONT LIFT BACK NORTHWARD A BIT AS A
WARM FRONT WITH A SLIGHT CHANCE FOR SOME STORMS ACROSS THE FAR
SOUTHWEST LATE MONDAY/MONDAY NIGHT. WAA THEN TO BEGIN AS THE FRONT
LIFTS NORTHWARD INTO THE STATE TUESDAY INTO WEDNESDAY. THIS OCCURS
IN RESPONSE TO A STRONGER SHORTWAVE TROUGH TOPPING THE WESTERN US
RIDGE AND PUSHING INTO THE NORTHERN PLAINS TUESDAY NIGHT INTO
WEDNESDAY. COULD SEE SOME LINGERING ACTIVITY INTO THURSDAY OR
FRIDAY AS THE FRONT HANGS UP ACROSS THE STATE BEFORE PUSHING BACK
SOUTH AS A STRONG COLD FRONT MOVES THROUGH THE STATE AND HIGH
PRESSURE BUILDS INTO THE GREAT LAKES/OHIO VALLEY REGION. THIS
SENDS H85 TEMPS DOWN TO AROUND +12C BY THE END OF NEXT WEEK INTO
NEXT WEEKEND. THEREFORE EXPECT GRADUAL COOLING THROUGH THE
WEEK...WITH TEMPS FALLING BACK TO NEAR OR SLIGHTLY BELOW THE
SEASONAL AVERAGES FOR THE BEGINNING OF THE WEEK. THEN TEMPS COOL
EVEN FURTHER TO BELOW THE SEASONAL AVERAGE WITH HIGHS MAINLY IN
THE 70S BY THE END OF THE WEEK INTO THE WEEKEND.

&&

.AVIATION...02/06Z
ISSUED AT 1117 PM CDT SAT AUG 1 2015

REMOVED MENTION OF SHRA/TSRA OVERNIGHT FROM THE TERMINALS. LATEST
INDICATIONS ARE THAT SUPPORT WILL NOT BE EXISTENT FOR PCPN
OVERNIGHT. THUS...VFR CIGS AND VSBYS ARE EXPECTED. WINDS WILL BE
HIGHER ON SUNDAY THAN TODAY. SLIGHT CHANCE OF SHRA/TSRA LATE AFTN
AND EVENING ACROSS EASTERN IA...BUT HAVE NOT ADDED MENTION TO THE
KALO OR KOTM TERMINALS ATTM.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

SHORT TERM...REV
LONG TERM...BEERENDS
AVIATION...ZOGG

Hazardous weather outlook, Aug 1, 3:23 PM CDT, 13 hours 14 minutes before

<!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>

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 2, 5:06 AM CDT	Special Weather Statement	DMX	Calhoun, Carroll, Greene	54 min
Aug 2, 5:35 AM CDT	Special Weather Statement	DMX	Wayne	40 min
Aug 2, 6:35 AM CDT	Special Weather Statement	DMX	Story	55 min
Aug 2, 5:02 PM CDT	Special Weather Statement	DMX	Adair, Madison, Warren	58 min
Aug 2, 5:07 PM CDT	Severe Thunderstorm Warning	DMX	Adair	38 min
Aug 2, 5:22 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Madison, Polk, Warren	38 min
Aug 2, 5:45 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Madison, Union	45 min
Aug 2, 5:48 PM CDT	Special Weather Statement	DMX	Adams	57 min
Aug 2, 6:00 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Madison, Warren	45 min
Aug 2, 6:07 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Cass	38 min
Aug 2, 6:11 PM CDT	Special Weather Statement	DMX	Marion	64 min
Aug 2, 6:18 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion	42 min
Aug 2, 6:26 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Clarke, Madison, Ringgold, Union	49 min
Aug 2, 6:30 PM CDT	Tornado Warning Tornado observed	DMX	Adams	30 min
Aug 2, 6:41 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Madison, Warren	49 min
Aug 2, 6:55 PM CDT	Tornado Warning Tornado observed	DMX	Adams, Union	18 min
Aug 2, 6:58 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska	23 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2015 Every severe thunderstorm warning in 2015

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.