Alert archive / Iowa / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 149, NWS Quad Cities, IA

September 18, 2007Buchanan County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Sep 18, 2007, 6:31 PM CDT for Buchanan County, Iowa. It was in force for 38 min. 1 report 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: Sep 18, 2007, 6:31 PM CDT (23:31 UTC)
Expired: Sep 18, 2007, 7:09 PM CDT
In force: 38 min
Issued by: NWS Quad Cities, IA
Area: Counties, with a storm outline in the text

County Buchanan County, IA

The radar

The Quad Cities radar (KDVN), 144 km from the middle of the area, began a volume at 23:32 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
Sep 18, 6:42 PM CDT	TSTM WND GST 60	Independence, IA	AT JUNCTION OF HIGHWAY 20 AND HIGHWAY 150 AT WALMART STORE.

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 11 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

Davenport, (KDVN), launched 12:00Z, 11.5 hours before the alert went out and 149 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1486 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 168 m²/s²
0-3 km storm-relative helicity: 184 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.

000 
WUUS53 KDVN 182330
SVRDVN
IAC019-190015-
/O.NEW.KDVN.SV.W.0149.070918T2331Z-070919T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
631 PM CDT TUE SEP 18 2007

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BUCHANAN COUNTY IN NORTHEAST IOWA...

* UNTIL 715 PM CDT.

* AT 628 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN
  EXCESS OF 70 MPH.  THIS STORM WAS LOCATED APPROXIMATELY 12 MILES
  SOUTH OF BRANDON...OR ABOUT NEAR VINTON...AND MOVING NORTHEAST AT
  70 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  BRANDON AROUND 640 PM CDT...
  ROWLEY AROUND 645 PM CDT...
  WINTHROP...QUASQUETON AND 6 MILES SOUTHEAST OF INDEPENDENCE AROUND
  650 PM CDT...
  LAMONT AND 6 MILES SOUTHEAST OF AURORA AROUND 700 PM CDT...

WIND DAMAGE WILL OCCUR BEFORE THUNDER CAN BE HEARD OR RAIN BEGINS.
SEEK SHELTER IMMEDIATELY.

THIS STORM HAS ALREADY PRODUCED WIND DAMAGE AND/OR LARGE HAIL...AND
IT REMAINS A THREAT.

LAT...LON 4263 9207 4264 9162 4244 9162 4230 9177
      4230 9206
TIME...MOT...LOC 2331Z 217DEG 62KT 4219 9203

$$

ERVIN

2 follow-up statements

000 
WWUS53 KDVN 182348
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
648 PM CDT TUE SEP 18 2007

IAC019-190015-
/O.CON.KDVN.SV.W.0149.000000T0000Z-070919T0015Z/
BUCHANAN IA-
648 PM CDT TUE SEP 18 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM CDT
FOR BUCHANAN COUNTY...

AT 645 PM CDT...TRAINED SPOTTERS REPORTED A SEVERE THUNDERSTORM 
CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH IN 
INDEPENDENCE. THIS STORM WAS LOCATED APPROXIMATELY NEAR THREE ELMS 
COUNTY PARK...OR ABOUT NEAR INDEPENDENCE...MOVING NORTHEAST AT 65 
MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  LAMONT AND AURORA AROUND 655 PM CDT...

WIND DAMAGE WILL OCCUR BEFORE THUNDER CAN BE HEARD OR RAIN BEGINS.
SEEK SHELTER IMMEDIATELY.

THIS STORM HAS ALREADY PRODUCED WIND DAMAGE AND/OR LARGE HAIL...AND
IT REMAINS A THREAT.

LAT...LON 4263 9207 4264 9162 4244 9162 4230 9177
      4230 9206
TIME...MOT...LOC 2348Z 220DEG 57KT 4249 9177

$$

ERVIN

000 
WWUS53 KDVN 190009
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
709 PM CDT TUE SEP 18 2007

IAC019-190019-
/O.CAN.KDVN.SV.W.0149.000000T0000Z-070919T0015Z/
BUCHANAN IA-
709 PM CDT TUE SEP 18 2007

...THE SEVERE THUNDERSTORM WARNING FOR BUCHANAN COUNTY IS
CANCELLED...

THE SEVERE THUNDERSTORM THAT PRODUCED DAMAGING WINDS HAS MOVED OUT 
OF THE WARNED AREA. THEREFORE THE SEVERE THUNDERSTORM WARNING HAS 
BEEN CANCELLED.

HOWEVER...THIS STORM IS STILL CAPABLE OF PRODUCING HEAVY RAIN.

LAT...LON 4263 9207 4264 9162 4244 9162 4230 9177
      4230 9206
TIME...MOT...LOC 0009Z 220DEG 57KT 4274 9148

$$

ERVIN

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 Quad Cities, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 18, 3:00 PM CDT, 3 hours 31 minutes earlier.

Area forecast discussion, Sep 18, 3:00 PM CDT, 3 hours 31 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
300 PM CDT TUE SEP 18 2007

.SYNOPSIS...
LATEST SFC ANALYSIS WAS INDICATING FRONTAL COMPLEX EXTENDING FROM
NORTHWEST ONTARIO TO A WEAK SFC WAVE OVER FAR SOUTHWEST MN...THEN
EXTENDING INTO SOUTHWEST CO. BROAD PRESSURE FALLS WERE LOCATED TO
THE LEE OF THIS FEATURE...WITH MOST PRONOUNCED AREA IN FAR EASTERN
KS JUST EAST OF THE MOST DECENT CONVECTIVE SYSTEM IN THE MIDWEST.
W/V IMAGERY WAS INDICATING MAIN UPSTREAM WAVE OF CONSEQUENCE ROLLING
ACRS FAR NORTHWEST KS AND THE NEB PANHANDLE.

&&

.SHORT TERM...TONIGHT AND WEDNESDAY...PREFER THE 12Z GFS IN SPEED AND
HANDLING OF INCOMING FRONT...ESPECIALLY NOW LOOKING AT THE NEW 12Z
HI-RES ECMWF WHICH GENERALLY AGREES WITH THE GFS. PLACEMENT OF STOUT
LOW TO MID LEVEL RIDGING ACRS THE SOUTHEAST AND EASTERN CONUS WILL
DEFLECT THE WESTERN NEB VORT TO THE NORTHEAST AND THE BULK OF ITS
CVA/FORCING WITH IT TONIGHT. MOST OF THE SHORT RANGE MODELS SHIFT
LIFT MAX/POS OMEGAS FROM NORTHWEST INTO NORTH CENTRAL IOWA THIS
EVENING...UP THROUGH NORTHWEST WI AND THEN DAMPENS THIS PROCESS AS
IT MIGRATES EASTWARD OVERNIGHT INTO THE LOCAL FCST AREA. MIXING IN
INSOLATION SECTOR JUST EAST-SOUTHEAST OF MAIN SHOWER/CLOUD SHIELD
OVER EASTERN IA AND NORTHEAST MO HAS KEPT A LID ON SFC DPTS...BUT
HEATING HAS MADE FOR RATHER STEEP LOW TO MID LEVEL LAPSE RATES. IF
A FEW STORMS COULD DEVELOP AND MAKE IT INTO THE WEST CENTRAL OR
NORTHEAST CWA THROUGH BEFORE 02Z OR SO...PROGGED LINGERING DOWNDRAFT
CAPES SUGGEST THAT A STORM MAY BE ALLOWED TO MIX DOWN SOME OF THE
BRISK AMBIENT LOW TO MID LEVEL WIND FIELD JUST TO THE LEE OF THE
FRONTAL COMPLEX...WITH INSTABILITY REALLY WANING AFTER THAT. EVEN
THOUGH SVR RISK LOOKS RATHER BLEAK...SOME MID LEVEL INSTABILITY
IS SUGGESTED BY THE MODELS TO HOLD ON ALONG AND WEST OF THE MS RVR
TO KEEP SHOWERS AND EMBEDDED THUNDER GOING THROUGH 06Z OR SO BEFORE
THAT PARAMETER ALONG WITH ANY LINGERING FORCING WANE. THUS EXPECT
SHOWERS AND SOME STORMS TO FALL APART AFTER MIDNIGHT EAST OF THE MS
RVR...AND WILL TAPER OFF POPS ACCORDINGLY. WHILE THE NORTHWEST
THIRD OF THE DVN CWA MAY RECEIVE FROM .25 UP TO HALF INCH OF
RAINFALL ROUGHLY THROUGH 07Z/2 AM CDT...MUCH OF THE REST OF THE FCST
AREA PROBABLY WILL RECEIVE A TENTH OF AN INCH OR LESS.

ON WED...FRONT TO WEAKEN AND SLOWS AS IT ENCOUNTERS DEEPER RIDGING TO
THE SOUTHEAST...POSSIBLY TAKING MUCH OF THE DAY TO CLEAR THE CWA. A
FEW LINGERING POST FRONTAL SHOWERS MAY OCCUR THROUGH EARLY AFTERNOON
ACRS THE SOUTHEAST HALF OF THE FCST AREA...BUT EXPECT SOME CLEARING
ACRS THE NORTHWEST HALF. SOME LAG IN BETTER LLVL CAA SUGGESTS ANY
CLEARING WITH SOME MIXING MAY HELP TEMPS RISE BACK TO AROUND 80 OR
EVEN THE LOW 80S...BUT AREAS THAT REMAIN CLOUD COVERED WILL BE
LIMITED TO THE 70S.     ..12..

.LONG TERM...TUESDAY NIGHT THROUGH MONDAY...
ABOVE NORMAL TEMPERATURES TRENDING MORE ACTIVE AND WET BY EARLY NEXT
WEEK.

PRIMARY GUIDANCE MORE CONSISTENT RUN TO RUN HI-RES ECMWF AND GFS AND
ALSO GEFS.  SOME INPUTS FROM NMA-WRF AND UKMET LATE WEDNESDAY INTO
THURSDAY.

WEDNESDAY NIGHT...TRIMMED TEMPS AND DEWPOINTS A FEW DEGREES AS WEAK
SURFACE HIGH RESULTS IN EAST WIND FOR GENERALLY COMFORTABLE NIGHT.
THURSDAY...WARM BUT NOT TOO HUMID AS SFC WINDS SLOWLY BECOME SE
BY PM.  POTENTIAL FOR MIN TEMPS STILL A FEW DEGREES TOO MILD IF THE
CENTER OF SFC HIGH NEARBY FOR STRONGER RADIATIONAL COOLING.  KEPT
LOW CHANCE POPS THROUGH PERIOD NEAR IA/MO BORDER WITH FRONT NEARBY
AND WEAK CONVERGENCE.  THURSDAY NIGHT AND FRIDAY...WAA KICKS BACK IN
WITH HIGHER DEWPOINTS AHEAD OF NEXT FRONT LATE FRIDAY WITH VERY WARM
AND HUMID CONDITIONS AND BREEZY SW WINDS IN PM TO TAKE A BIT OFF THE
HEAT OFF OF 85 TO 90+F MAX TEMPS.  CONCERN IS POTENTIAL FOR STORMS
TO FIRE LATE FRIDAY AND FRIDAY NIGHT WITH NEXT FRONTAL PASSAGE...LEFT
DRY FOR NOW AND PASS FOR LATER SHIFTS TO CONSIDER.  SATURDAY...
ANOTHER WEAK FRONT TO PASS WITH EAST WINDS AND HAVE TRIMMED TEMPS
WHICH STILL MAY BE AT LEAST A FEW DEGREES TOO HIGH INTO SUNDAY
MORNING. SUNDAY...TEMPERATURES TO WARM BACK TO MID TO UPPER 80S TO
POSSIBLY NEAR 90.

MONDAY AND TUESDAY...LOTS OF MOISTURE FROM SOUTH PLAINS TO ARRIVE
FROM TROPICAL SYSTEM MOVING NORTH AHEAD OF APPROACHING UPPER TROUGH
AND HAVE UPPED CLOUDS AND LOWERED MAX TEMPS AND ALSO UPPER POPS TO 30
MON NIGHT. HIGH PW OF 1.5 TO 2 INCHES AND DECENT FORCING SUPPORT
SEASONALLY HEAVY RAIN AMOUNTS FOR LATER SHIFTS TO MONITOR AND UPDATE
ACCORDINGLY.  MAX TEMPS A COMPROMISE...DEFINITELY HIGH TEMPS TO BE
LOWER EARLY NEXT WEEK INTO REST OF NEXT WEEK.    ..NICHOLS..

&&

.AVIATION...
APPROACHING FRONTAL COMPLEX AND ASSOCIATED PRECIP WILL KNOCK DOWN
CONDITIONS AT THE CID/MLI/DBQ TERMINAL SITES TO AT LEAST MVFR FROM
04Z TO 11Z OR SO...BEFORE WIND SHIFT TO THE NORTHWEST BRINGS BACK
VFR CEILINGS AND VSBYS AFTER 14Z WED.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.

&&

12/NICHOLS

Hazardous weather outlook, Sep 18, 4:56 AM CDT, 13 hours 35 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
456 AM CDT TUE SEP 18 2007

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-191000-
BUCHANAN-DELAWARE-DUBUQUE-BENTON-LINN-JONES-JACKSON-IOWA-JOHNSON-
CEDAR-CLINTON-MUSCATINE-SCOTT-KEOKUK-WASHINGTON-LOUISA-JEFFERSON-
HENRY IA-DES MOINES-VAN BUREN-LEE-JO DAVIESS-STEPHENSON-CARROLL-
WHITESIDE-ROCK ISLAND-HENRY IL-BUREAU-PUTNAM-MERCER-HENDERSON-
WARREN-HANCOCK-MCDONOUGH-SCOTLAND-CLARK-
456 AM CDT TUE SEP 18 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL
ILLINOIS...NORTHWEST ILLINOIS...WEST CENTRAL ILLINOIS...EAST
CENTRAL IOWA...NORTHEAST IOWA...SOUTHEAST IOWA AND NORTHEAST
MISSOURI.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS WILL MOVE INTO THE OUTLOOK AREA LATE THIS AFTERNOON
AND EVENING AHEAD OF A COLD FRONT. THE STORM PREDICTION CENTER HAS
PLACED A SLIGHT RISK OF SEVERE STORMS WEST OF A LINE FROM
SIGOURNEY TO DUBUQUE IOWA. MODERATE INSTABILITY IS EXPECTED TO
DEVELOP THIS AFTERNOON AS TEMPERATURES ONCE AGAIN RISE INTO THE
MID 80S TO NEAR 90 TODAY...COMBINED WITH INCREASING HUMIDITY
LEVELS. THE GREATEST RISK WITH THESE STORMS IS FOR DAMAGING WINDS
AND HAIL.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE IS A CONTINUING CHANCE OF THUNDERSTORMS WEDNESDAY AND
WEDNESDAY NIGHT. AT THIS TIME THESE STORMS ARE NOT EXPECTED TO
PRODUCE SEVERE WEATHER.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE LATE THIS AFTERNOON AND EVENING
NORTHWEST OF A LINE FROM SIGOURNEY TO DUBUQUE.

In the hours before

Special weather statement, Sep 18, 5:40 PM CDT, 51 minutes before

IAZ040-051-052-063-076-182350-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
540 PM CDT TUE SEP 18 2007

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A SPECIAL
WEATHER STATEMENT EFFECTIVE UNTIL 645 PM CDT FOR THE FOLLOWING
COUNTIES...

IN IOWA
     BUCHANAN...BENTON...LINN...IOWA AND KEOKUK

INCLUDING...BUT NOT LIMITED TO THE FOLLOWING LOCATIONS
     BELLE PLAINE...INDEPENDENCE...MARENGO...NORTH ENGLISH...
     SIGOURNEY...STANLEY...URBANA...VAN HORNE...VINTON...
     WHAT CHEER...WILLIAMSBURG AND WINTHROP

AT 532 PM CDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS ALONG A LINE EXTENDING FROM 30 MILES NORTHWEST OF BELLE
PLAINE TO 43 MILES SOUTHWEST OF MARTINSBURG...OR ALONG A LINE
EXTENDING FROM 35 MILES SOUTHWEST OF WATERLOO TO 18 MILES NORTHWEST
OF LANCASTER...MOVING NORTHEAST AT 45 MPH.

ERVIN

Local storm report, Sep 18, 6:15 PM CDT, 16 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
615 PM CDT TUE SEP 18 2007

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

0613 PM     TSTM WND GST     BELLE PLAINE            41.90N 92.27W
09/18/2007  M60 MPH          BENTON             IA   EMERGENCY MNGR

            REPORTED BY EMA OFFICE.

&&

ELLIOTT

Local storm report, Sep 18, 6:23 PM CDT, 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
623 PM CDT TUE SEP 18 2007

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

0620 PM     TSTM WND GST     GARRISON                42.14N 92.14W
09/18/2007  M46 MPH          BENTON             IA   TRAINED SPOTTER

            STEADY WINDS AT 40 MPH. GUST TO 46 MPH.

&&

ELLIOTT

Local storm report, Sep 18, 6:24 PM CDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
624 PM CDT TUE SEP 18 2007

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

0621 PM     TSTM WND GST     VAN HORNE               42.01N 92.09W
09/18/2007  E60 MPH          BENTON             IA   EMERGENCY MNGR

            BY FIRE DEPARTMENT AT VAN HORNE.

&&

ELLIOTT

Local storm report, Sep 18, 6:26 PM CDT, 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
626 PM CDT TUE SEP 18 2007

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

0624 PM     TSTM WND GST     7 SW VINTON             42.09N 92.12W
09/18/2007  E65 MPH          BENTON             IA   EMERGENCY MNGR

            RELAYED BY EM. REPORTED BY TRAINED SPOTTER.

&&

ELLIOTT

Local storm report, Sep 18, 6:30 PM CDT, 1 minute before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
630 PM CDT TUE SEP 18 2007

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

0624 PM     TSTM WND GST     1 N VINTON              42.15N 92.03W
09/18/2007  M79 MPH          BENTON             IA   TRAINED SPOTTER

            STEADY WINDS AT 46 MPH.

&&

ELLIOTT

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 18, 6:01 PM CDT	Severe Thunderstorm Warning	DVN	Benton, Iowa	44 min
Sep 18, 6:36 PM CDT	Severe Thunderstorm Warning	DVN	Linn	39 min
Sep 18, 6:44 PM CDT	Severe Thunderstorm Warning	DVN	Delaware	42 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2007 Every severe thunderstorm warning in 2007

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.