Alert archive / Iowa / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 34, NWS Des Moines, IA

May 17, 2013Palo Alto County, Pocahontas County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 17, 2013, 6:39 PM CDT for Palo Alto County, Pocahontas County, Iowa. It was in force for 51 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 17, 2013, 6:39 PM CDT (23:39 UTC)
Expired: May 17, 2013, 7:30 PM CDT
In force: 51 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Palo Alto County, IA, Pocahontas County, IA

The radar

The Des Moines radar (KDMX), 155 km from the middle of the area, began a volume at 23:39 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.

What was reported inside it

Time	Report	Where	Remark
May 17, 6:45 PM CDT	HAIL 1.75	2 Wsw Curlew, IA	SHAVE REPORT
May 17, 6:55 PM CDT	HAIL 0.88	3 Wsw Curlew, IA	SHAVE REPORT
May 17, 7:00 PM CDT	HAIL 0.88	2 Wsw Curlew, IA	SHAVE REPORT

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 6 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.7 hours before the alert went out and 222 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: 183 J/kg
Mixed-layer CIN: -88 J/kg
Mixed-layer LCL: 1169 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

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

918 
WUUS53 KDMX 172339
SVRDMX
IAC147-151-180030-
/O.NEW.KDMX.SV.W.0034.130517T2339Z-130518T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
639 PM CDT FRI MAY 17 2013

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN PALO ALTO COUNTY IN NORTHWEST IOWA...
  NORTHWESTERN POCAHONTAS COUNTY IN NORTHWEST IOWA...

* UNTIL 730 PM CDT

* AT 634 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED 9 MILES NORTHEAST
  OF LAURENS...AND MOVING SOUTH AT 10 MPH.

  HAZARD...QUARTER SIZE HAIL.

  SOURCE...RADAR INDICATED.

  IMPACT...DAMAGE TO VEHICLES AND CROPS IS EXPECTED.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HAVELOCK AND LAURENS AROUND 715 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 4299 9458 4276 9461 4280 9492 4285 9492
      4305 9484
TIME...MOT...LOC 2339Z 011DEG 10KT 4294 9475

HAIL...1.00IN
WIND...<50MPH

$$

2 follow-up statements

414 
WWUS53 KDMX 180003
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
703 PM CDT FRI MAY 17 2013

IAC147-151-180030-
/O.CON.KDMX.SV.W.0034.000000T0000Z-130518T0030Z/
POCAHONTAS IA-PALO ALTO IA-
703 PM CDT FRI MAY 17 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
PALO ALTO AND NORTHWESTERN POCAHONTAS COUNTIES UNTIL 730 PM CDT...

AT 658 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED 6 MILES NORTHEAST
OF LAURENS...AND MOVING SOUTH AT 10 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...DAMAGE TO VEHICLES AND CROPS IS EXPECTED.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  LAURENS AROUND 730 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 4297 9487 4296 9470 4277 9470 4280 9492
      4285 9492
TIME...MOT...LOC 0004Z 015DEG 7KT 4290 9478

HAIL...1.00IN
WIND...<50MPH

$$

184 
WWUS53 KDMX 180025
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
725 PM CDT FRI MAY 17 2013

IAC147-151-180030-
/O.CON.KDMX.SV.W.0034.000000T0000Z-130518T0030Z/
POCAHONTAS IA-PALO ALTO IA-
725 PM CDT FRI MAY 17 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR SOUTHWESTERN
PALO ALTO AND NORTHWESTERN POCAHONTAS COUNTIES UNTIL 730 PM CDT...

AT 722 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR LAURENS...AND
MOVING SOUTH AT 10 MPH.

HAZARD...QUARTER SIZE HAIL.

SOURCE...RADAR INDICATED.

IMPACT...DAMAGE TO VEHICLES AND CROPS IS EXPECTED.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  LAURENS AROUND 730 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS!

&&

LAT...LON 4297 9487 4296 9470 4277 9470 4280 9492
      4285 9492
TIME...MOT...LOC 0025Z 015DEG 7KT 4286 9480

HAIL...1.00IN
WIND...<50MPH

$$

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 May 17, 3:59 PM CDT, 2 hours 40 minutes earlier.

Area forecast discussion, May 17, 3:59 PM CDT, 2 hours 40 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
359 PM CDT FRI MAY 17 2013

.SHORT TERM.../TONIGHT/
ISSUED AT 354 PM CDT FRI MAY 17 2013

AREAS OF SHOWERS AND THUNDERSTORMS WHICH HAVE DEVELOPED ACROSS
PORTIONS OF NORTHERN CWA ALONG WEAK BOUNDARY WILL PERSIST THROUGH
THE EVENING HOURS...AS SYSTEM CONTINUES TO PUSH SLOWLY EASTWARD.
ANTICIPATE DEVELOPMENT TO TAPER OFF AFTER PEAK HEATING...BUT WILL
CONTINUE TO SEE ISOLATED THUNDERSTORMS. VERY LIMITED SHEAR WITH
STORMS...AND DO NOT ANTICIPATE SEVERE WEATHER...THOUGH A STORM MAY
BRIEFLY PRODUCE HAIL OR GUSTY WINDS. IN ADDITION...STORMS HAVE BEEN
EFFICIENT RAINFALL PRODUCERS...AND MAY SEE A RISK FOR FLASH FLOODING
ACROSS THE NORTH WERE SOILS ARE SATURATED...IF STORMS TRAIN OR MOVE
SLOWLY ACROSS THE REGION. WILL NOT PUT OUT A FLASH FLOOD WATCH GIVEN
THE ISOLATED NATURE OF STORMS. PRECIPITATION CHANCES WILL DIMINISH
THROUGH 06Z AS SYSTEM LIFTS NORTHEAST. OVERNIGHT LOWS AGAIN ARE
TRICKY WITH CLOUD COVER. HAVE DROPPED TEMPERATURES A FEW DEGREES
ACROSS THE NORTHEAST WHERE HIGH TEMPERATURES WERE COOLER WITH CLOUD
COVER. SOME STRONGER WAA BEGINS TO PUSH INTO THE WEST LATE IN THE
OVERNIGHT...AND MAY SEE SLIGHTLY WARMER TEMPERATURES THERE...HOWEVER
HAVE KEPT TEMPS BELOW GUIDANCE THERE.

.LONG TERM.../SATURDAY THROUGH FRIDAY/
ISSUED AT 354 PM CDT FRI MAY 17 2013

PRIMARY CONCERN REMAINS PRECIP TRENDS THROUGH THE
PERIOD...ESPECIALLY SUNDAY INTO MONDAY. THE WEEKEND WILL BEGIN
FAIRLY TRANQUIL HOWEVER WITH WARM AND HUMID WEATHER AS IA IS
INFLUENCED BY THE WARM SECTOR. THETA-E ADVECTION WILL SPREAD SW-
NE INTO SAT NIGHT HOWEVER INCREASING OUR CHANCES FOR
CONVECTION.,.WHICH LOOKS LIKE IT WILL LINGER INTO AT LEAST SUNDAY
MORNING. STEEP LAPSE RATES AND SOME FORM OF AN ELEVATED MIXED
LAYER EARLY MAY KEEP THE CONVECTION QUITE ELEVATED
INITIALLY...HOWEVER SOUNDINGS SHOW THE COLUMN MOISTENING TOWARD
DAYBREAK. MORE FAVORABLE CAPE/CIN PARCELS LOWER IN SOUNDINGS
LEADING TO CONVECTION POTENTIALLY BEING ROOTED LOWER INTO SUNDAY.
ESTIMATED EFFECTIVE SHEAR IS NOT GREAT AT THIS POINT...BUT WOULD
STILL BE SUFFICIENT FOR LOW END SEVERE THREAT CONSIDERING MUCAPES
APPROACHING 2000 J/KG AT TIMES.

THIS LEADS INTO LATER SUNDAY WHERE SOME QUESTIONS ABOUT SURFACE
BASED EVENT COMING TOGETHER STILL EXIST. THETA-E ADVECTION STILL
LINGERS INTO IA BY MIDDAY LEADING TO QUESTIONS RAISED YESTERDAY
REGARDING RECOVERY TIME BETWEEN ELEVATED CONVECTION AND PEAK HEATING
SURFACE BASED POTENTIAL. MODELS ARE STILL IN SOME DISAGREEMENT
WITH REGARD TO PLACEMENT OF SURFACE FEATURES AS WELL...ON BOTH THE
SYNOPTIC AND MESOSCALE. 12Z GFS AND ECMWF FAVOR A SURFACE LOW
BEING CENTERED OVER ERN NE...WHILE 12Z NAM SUGGESTS LOWER PRESSURE
FROM NE INTO MN ALONG INVERTED TROUGH. NAM ALSO SHOW FRONT
ENHANCED BY OUTLOW ACROSS MO. THIS OUTFLOW FROM EARLIER
CONVECTION COULD VERY WELL AFFECT NORTHWARD EXTENT OF
THERMODYNAMIC RECOVERY AND WHERE LOCALIZED 0-1KM SHEAR AND TORNADO
THREAT IS ENHANCED. EVEN WITH THESE QUESTIONS IT STILL APPEARS
THAT CURRENT SPC DAY 3 OUTLOOK HAS FAVORED AREA IN PLACE WHICH IS
ON THE NOSE OF THE UPPER LEVEL JET AND POTENTIAL FOR BETTER DEEP
SHEAR. LOOKED AT SLU CIPS 12Z ANALOGS TO SEE IF THEY OFFERED ANY
INSIGHT...BUT 60HR FORECAST UTILIZES THE NAM AS A BASELINE WHICH
MAY BE TOO FAR NORTH WITH SURFACE FEATURES. 00Z GFS ANALOGS MAY BE
TOO FAR NORTH AS WELL...AS GFS HAS NOW TRENDED CLOSER TO PREVIOUS
ERN NE ECMWF SOLUTIONS.

SITUATION CHANGES SOMEWHAT MONDAY WITH LOWER DEWPOINTS DROPPING
INSTABILITY SOMEWHAT AS WELL. SOUNDINGS APPEAR WELL MIXED WITH
LITTLE CINH HOWEVER SO STILL EXPECT CONVECTION TO DEVELOP
DIURNALLY. DAMAGING WINDS POTENTIAL MAY BE SOMEWHAT HIGHER DUE TO
STRONGER MIXED LAYER WINDS AND BETTER DCAPES AS LOW LAYERS DRY OUT
SOMEWHAT. SYSTEM THEN OCCLUDES INTO TUE AND IS IN NO HURRY TO
DEPART. MID/LATE MAY SOLAR HEATING NEAR THIS UPPER LOW WILL KEEP
POTENTIAL FOR MAINLY DIURNALLY BASED CONVECTION IN THE FORECAST TO
SOME EXTENT UNTIL THU WHEN SYSTEM FINALLY OPENS UP AND EXITS.

&&

.AVIATION...17/18Z
ISSUED AT 1217 PM CDT FRI MAY 17 2013

CEILINGS WILL REMAIN PRIMARILY VFR...WITH ISOLATED THUNDERSTORMS
BETWEEN18-00Z WHICH MAY BRING LOWER MVFR CEILINGS TO
SITES...ESPECIALLY NORTHERN SITES KFOD/KMCW/KDSM. HOWEVER...IMPACT
WILL BE BRIEF. HAVE INCLUDED MENTION OF VCTS...WITH ISOLATED
NATURE OF STORMS. CEILINGS WILL BE LIFTING AS SYSTEM PUSHES
FURTHER EAST WITH WINDS BECOMING MORE SOUTHERLY AND LIGHT
OVERNIGHT.

&&

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

&&

SHORT TERM...AWB
LONG TERM...SMALL
AVIATION...AWB

Hazardous weather outlook, May 17, 3:27 PM CDT, 3 hours 12 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
327 PM CDT FRI MAY 17 2013

IAZ070>075-081>086-092>097-182030-
CASS-ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-
MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS-
327 PM CDT FRI MAY 17 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

PERIODS OF THUNDERSTORMS ARE FORECAST SATURDAY NIGHT THROUGH
TUESDAY. THERE IS A THREAT FOR SEVERE WEATHER SATURDAY NIGHT THROUGH
MONDAY WITH THE MOST SIGNIFICANT POTENTIAL SUNDAY AFTERNOON AND
EVENING. VERY LARGE HAIL...DAMAGING WINDS AND A FEW TORNADOES ARE
POSSIBLE SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED SUNDAY AFTERNOON AND EVENING.

IAZ004>007-015>017-023>028-033>039-044>050-057>062-182030-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-BUTLER-BREMER-SAC-CALHOUN-
WEBSTER-HAMILTON-HARDIN-GRUNDY-BLACK HAWK-CRAWFORD-CARROLL-GREENE-
BOONE-STORY-MARSHALL-TAMA-AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-
POWESHIEK-
327 PM CDT FRI MAY 17 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY THROUGH THIS EVENING.
THE PRIMARY THREAT IS HEAVY RAINFALL THAT COULD PRODUCE LOCAL
FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

PERIODS OF THUNDERSTORMS ARE FORECAST LATE SATURDAY NIGHT THROUGH
TUESDAY. THERE IS A THREAT FOR SEVERE WEATHER SATURDAY NIGHT
THROUGH MONDAY WITH THE MOST SIGNIFICANT POTENTIAL SUNDAY
AFTERNOON AND EVENING. LARGE HAIL...DAMAGING WINDS AND AN ISOLATED
TORNADO ARE POSSIBLE SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED SUNDAY AFTERNOON AND EVENING.

AWB

In the hours before

Special weather statement, May 17, 5:17 PM CDT, 1 hour 22 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
517 PM CDT FRI MAY 17 2013

IAZ015-172245-
PALO ALTO-
517 PM CDT FRI MAY 17 2013

...THUNDERSTORMS PRODUCING VERY HEAVY RAIN AND HAIL...

AT 513 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM OVER CENTRAL PALO ALTO COUNTY...MOVING SOUTH AT 5
MPH.

PENNY SIZE HAIL...WINDS GREATER THAN 30 MPH...VERY HEAVY
DOWNPOURS...ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
    RURAL PALO ALTO COUNTY AT 530 PM CDT

GUSTY WINDS MAY CAUSE SMALL OBJECTS SUCH AS TRASH BINS TO BLOW
AROUND. SEEK SHELTER IN A STURDY STRUCTURE UNTIL THIS STORM HAS
PASSED.

Local storm report, May 17, 5:32 PM CDT, 1 hour 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
532 PM CDT FRI MAY 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0527 PM     HAIL             1 W EMMETSBURG          43.11N 94.70W
05/17/2013  E1.00 INCH       PALO ALTO          IA   PUBLIC

            PUBLIC REPORT OF HEAVY RAINFALL ALONG WITH NICKEL TO A
            FEW QUARTER SIZED HAILSTONES.

&&

FBOKSA

Local storm report, May 17, 5:46 PM CDT, 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
546 PM CDT FRI MAY 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0526 PM     HAIL             EMMETSBURG              43.11N 94.68W
05/17/2013  E0.50 INCH       PALO ALTO          IA   TRAINED SPOTTER

&&

BBROCK

Local storm report, May 17, 5:53 PM CDT, 46 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
553 PM CDT FRI MAY 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0548 PM     FLASH FLOOD      EMMETSBURG              43.11N 94.68W
05/17/2013                   PALO ALTO          IA   LAW ENFORCEMENT

            SEVERAL INCHES OF WATER FLOWING OVER THE ROAD IN
            EMMETSBURG AT LAWLER AND MAIN.

&&

FBOKSA

Local storm report, May 17, 6:16 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
616 PM CDT FRI MAY 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0615 PM     HEAVY RAIN       EMMETSBURG              43.11N 94.68W
05/17/2013  M1.25 INCH       PALO ALTO          IA   TRAINED SPOTTER

&&

BBROCK

Local storm report, May 17, 6:27 PM CDT, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
627 PM CDT FRI MAY 17 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0624 PM     HEAVY RAIN       2 N EMMETSBURG          43.14N 94.68W
05/17/2013  M5.00 INCH       PALO ALTO          IA   BROADCAST MEDIA

            VERY HEAVY RAINFALL IN ONE HOUR REPORTED TO KICD

&&

BBROCK

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 7:05 PM CDT	Flash Flood Warning	DMX	Carroll, Crawford	6 hr
May 17, 3:40 AM CDT	Flash Flood Warning	DMX	Hancock, Kossuth, Winnebago	6 hr
May 17, 4:55 PM CDT	Flash Flood Warning	DMX	Palo Alto	4 hr
May 17, 5:29 PM CDT	Severe Thunderstorm Warning	DMX	Palo Alto	46 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2013 Every severe thunderstorm warning in 2013

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.