Alert archive / Iowa / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 16, NWS Quad Cities, IA

May 16, 1999Buchanan County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at May 16, 1999, 6:00 PM CDT for Buchanan County, Iowa. It was in force for 45 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 16, 1999, 6:00 PM CDT (23:00 UTC)
Expired
May 16, 1999, 6:45 PM CDT
In force
45 min
Issued by
NWS Quad Cities, IA
Area
Whole counties

County Buchanan County, IA

The radar

The Quad Cities radar (KDVN), 141 km from the middle of the area, began a volume at 23:04 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

TimeReportWhereRemark
May 16, 6:05 PM CDTHail 1Fairbank, IA
May 16, 6:40 PM CDTHail 0.88Fairbank, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
May 16, 2:15 PM CDTSevere Thunderstorm WatchSPC6 hr
May 16, 4:45 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 11.0 hours before the alert went out and 145 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 1999-05-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 266 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 1999-05-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
266 J/kg
Mixed-layer CIN
-240 J/kg
Mixed-layer LCL
780 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
138 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 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 May 16, 2:30 PM CDT, 3 hours 30 minutes earlier.

Area forecast discussion, May 16, 2:30 PM CDT, 3 hours 30 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
230 PM CDT SUN MAY 16 1999

CURRENT MSAS AND RUC DATA INDICATING ONGOING CONVECTION PUSHING INTO FAR
NORTHEAST IA ATTM RIDING NICELY ALONG SFC-H85 THTA-E GRADIENT DRAPED
ACRS CENTRAL IA. ACTIVITY ALSO PUSHING MORE EASTWARD ALONG WITH
SOMEWHAT DIFFLUENT 15Z RUC H7-H3 THICKNESS FIELDS. MSAS AND 18Z SFC
OBS INDICATING SOUTHWEST HALF OF IA...NORTHWEST MO AND SOUTHEAST NE
DESTABILIZING QUICKLY WITH LOW LEVEL MOISTURE CONVERGENCE...POOLING
UPPER 60 TO LOWER 70 DPTS...AND SOME INSOLATION. 12Z H85 ANALYSIS
AND PROFILER DATA ALSO INDICATING IMPRESSIVE LLJ PUNCHING ACRS PLAINS
INTO NORTHWEST MO AND SOUTHWEST IA.

NGM ACTUALLY HANDLING 18Z SFC FEATURES BEST WITH FRONTAL POSITION FROM
WEST MN INTO CENTRAL KS...AND WEAK WAVE OVER SOUTHEAST NE. APPEARS
SOUTHEAST NE AND EASTERN KS AREAS READY TO GO WITH CONTINUING SFC-H85
THTA-E ADVECTION AND CONVERGENCE. NGM PAINTING BEST H85 THTA-E
ADVECTION INITIALLY THIS EVENING ACRS NORTHERN IA...AS WELL AS EAST KS
INTO NORTHWEST MO. FEEL THE LATER AREA READY TO GO. H85-H3 THICKNESS
PROGGED TO BE DIFFLUENT ACRS GENERAL AREA...IN GENERAL EAST-SOUTHEAST
TRANSLATION OF CONVECTIVE SYSTEM ACRS SOUTHERN IA AND NORTHERN MO. ETA
FURTHER SOUTH AND SOUTHEAST WITH SIMILAR PARAMETERS WITH BEST
INSTABILITY AXIS ACRS KS INTO WEST MO. IN ANY CASE...AREA TO BE AT
RISK OVERNIGHT WITH EVENTUAL UPSTREAM ACTIVITY AND POSSIBLE HEAVY RAIN
TO BLEED ACRS AREA LATE TONIGHT. STRONG THTA-E ADVECTION AND LLJ TO
SHIFT TOWARD EAST IA AND SOUTHWEST WI AS NIGHT PROGRESSES TO CONTINUE
FEEDING ACTIVITY. SCATTERED STRONG TO SEVERE ACTIVITY POSSIBLE
EARLY TONIGHT...ESPECIALLY WITH ONGOING DESTABILIZATION NORTH OF WARM
FRONT LYING NEAR IA/MO BORDER. WILL NOT GO WITH FLOOD WATCH AS OF YET...
ALTHOUGH WATER TROUBLE VERY POSSIBLE LATER TONIGHT AS ACTIVITY EVOLVES
INTO HEAVY RAIN EVENT.

THUNDERSTORM ACTIVITY TO CONTINUE MONDAY AS FRONTAL BOUNDARY CLOSES IN
ACRS CENTRAL IA AND MAIN H5 VORT APPROACHES. SHORT RANGE MODELS DIFFER
IN TIMING SOMEWHAT WITH FROPA AND MAIN VORT SWINGING ACRS EAST
IA/NORTHWEST IL MON EVENING AND NIGHT. ETA QUICKEST...WILL LEAN TO AVN
BEST GENERAL SOLUTION WITH PRECIP ENDING BY 12Z TUES.

QUICKLY LOOKING FURTHER AHEAD...
SFC AND UPPER RIDGING TO CONTINUE TO CREATE DRY WEATHER THROUGH THURSDAY
...ALTHOUGH EUROPEAN QUICKER TO SWING WAVE THROUGH IN NORTHERN STREAM
AND RAIN CHANCE THURSDAY. MRF HOLDS PRECIPITATION ACTIVITY OFF UNTIL
MAYBE FRI AS NORTHERN STREAM S/W PHASES WITH WAVE EJECTING OUT IN
WEAKER SOUTHERN STREAM FROM LARGE CUTOFF LOW IN THE SOUTHWEST CONUS. MAY
STILL KEEP FRI DRY FOR NOW. GOTTA GO AS ACTIVITY INFLAMMING NEAR
NORTHWEST DVN CWA.

COORDINATED WITH DMX...THANX.

.DVN...
IA...NONE.
IL...NONE.

JDH

In the hours before

Special weather statement, May 16, 12:17 PM CDT, 5 hours 43 minutes before
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Special weather statement, May 16, 12:55 PM CDT, 5 hours 5 minutes before
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Local storm report, May 16, 2:58 PM CDT, 3 hours 2 minutes before
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Local storm report, May 16, 2:58 PM CDT, 3 hours 2 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
May 16, 2:36 PM CDTSevere Thunderstorm WarningDVNBuchanan44 min
May 16, 6:43 PM CDTSevere Thunderstorm WarningDVNBuchanan47 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1999Every severe thunderstorm warning in 1999

Sources

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