Hail and Heavy Rain in Iowa, July 23, 2009

Name: Hail and Heavy Rain in Iowa, July 23, 2009
Start: 2009-07-23T04:00
End: 2009-07-23T05:08
Location: Iowa

July 23, 2009 · NWS DMX · 4 events in 2 counties and zones

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $6,000
Crop damage: $60,000
Events: 4

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS DMX wrote it up.

The thunderstorms that formed in the instability during the previous evening continued through the night as an elevated pulse type situation. Weak low pressure developed over southeast Iowa, giving a slight enhancement in the low level convergence during the predawn hours. One thunderstorm became severe as it passed southeast near Chariton in Lucas County. The cell dropped three quarter inch diameter hail as it moved through Charition. About 2 inches of rain fell in under one half hour as well, causing creeks to reach bankfull stage. The storm became severe in Appanoose County and dropped one inch diameter hail north of Plano. Hail fell west of Rathbun Lake and cut a three quarter mile wide swath. Damage was done to a pickup truck and crops were destroyed along the path. Hail accumulated to the point that hail was still on the ground 8 hours after the event.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jul 23, 2:19 AM CST, 1 hour 41 minutes earlier.

Area forecast discussion, Jul 23, 2:19 AM CST, 1 hour 41 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
319 AM CDT THU JUL 23 2009

.SHORT TERM.../TODAY/
S/WV IS CURRENTLY DROPPING SEWD ACRS THE CWA ANDC SONT TO SENT OFF A
FEW TSRA.  MAIN AREA HAS SHIFTED S OF I-80 NOW AND WILL CARRY ISOLD
POPS OVR THE SRN THIRD THIS MRNG AND KEPT A SMALL POP OVR THE FAR
SERN ZNS THIS AFTN.  FEELING IS THAT WELL AVOID A REPEAT OF TSRA
DVLPMT THAT WEVE SEEN THE PAST COUPLE DAYS SINCE THE AMS IS BCMG A
BIT DRIER AND ALSO RDGG ALF IS SLATED TO MOV INTO THE STATE DURG THE
DAY.  RISING HGTS AND H7 TEMPS ARE NOT ALL THAT CONDUCIVE FOR
DVLPMT.  WENT FOR TEMPS SIM TO THOSE OF YDA.

.LONG TERM.../TONIGHT THROUGH WEDNESDAY/
PRIMARY FORECAST ISSUE REMAINS THE LARGE CYCLONE BARRELING SOUTHEAST
FROM SOUTHERN CANADA INTO THE GREAT LAKES REGION FRIDAY AND
SATURDAY. FORECAST THINKING HAS CHANGED VERY LITTLE OVER THE LAST
COUPLE OF DAYS...WITH PROGNOSTIC MODELS STEADILY COMING INTO BETTER
AGREEMENT REGARDING THE DETAILS OF TIMING AND SO FORTH. SURFACE HIGH
WILL MOVE OFF TO THE SOUTHEAST TONIGHT WITH LIGHT SOUTHERLY BREEZES
KICKING IN BY FRIDAY MORNING. COLD FRONT WILL ENTER OUR NORTHERN
COUNTIES FRIDAY AFTERNOON AND MOVE QUICKLY ACROSS OUR AREA THROUGH
THE EVENING. AHEAD OF THE FRONT WINDS WILL VEER TO SOUTH SOUTHWEST
AND SOUTHWEST...ENHANCING WARM AIR ADVECTION. WITH THE FRONT NOT
ENTERING THE MAJORITY OF THE STATE UNTIL AFTER PEAK HEATING HAVE
CONTINUED UPWARD TREND IN MAX TEMP FORECAST FOR FRIDAY...WITH LOWER
90S ACROSS OUR SOUTHWEST NOW. IF SURFACE FLOW IS STRONGER THAN
FORECAST AND/OR CLOUD COVER IS LESS...TEMPS WILL LIKELY HAVE TO COME
UP EVEN MORE AS WE COULD CERTAINLY HIT LOWER 90S IN THE DES MOINES
METRO.

AS THE FRONT PROGRESSES ACROSS OUR AREA FRIDAY AFTERNOON AND EVENING
THE THREAT FOR THUNDERSTORMS WILL INCREASE. AHEAD OF THE FRONT A
GOOD AMOUNT OF LIFT WILL BE MITIGATED BY CAPPING AND LACK OF A FOCUS
MECHANISM...SO AM NOT OVERLY OPTIMISTIC ABOUT POPS MUCH AHEAD OF THE
FRONT. SURFACE CONVERGENCE ALONG THE BOUNDARY WILL BE THE PRIMARY
FOCUS FOR THUNDERSTORM DEVELOPMENT...ESPECIALLY ACROSS THE
NORTHEASTERN HALF OF OUR AREA WHERE DYNAMICS WILL BE MORE FAVORABLE
CLOSER TO THE MID/UPPER LOW. THERE SHOULD BE A GOOD AMOUNT OF
CONDITIONAL INSTABILITY BENEATH THE CAP IN THE AFTERNOON...SO ONCE
STORMS BREAK THROUGH ALONG THE FRONT CONDITIONS MAY BE FAVORABLE FOR
SEVERE WEATHER. SPC HAS PLACED US IN A SLIGHT RISK WHICH SEEMS
APPROPRIATE. FOR NOW HAVE HELD OFF ON INTRODUCING LIKELY POPS FOR
FRIDAY/FRIDAY NIGHT ONLY BECAUSE OF ISSUES REGARDING TIMING OF THE
FRONT/CONVECTION CROSSING THE 00Z THRESHOLD...BUT HAVE INCREASED TO
AROUND 50 POP ACROSS MUCH OF OUR NORTHEAST AND EAST.

BEHIND THE FRONT FROM FRIDAY NIGHT THROUGH AT LEAST SATURDAY NIGHT
WE WILL REMAIN IN NORTHWESTERLY FLOW IN A COLD AIR ADVECTION
REGIME...WITH STRATUS/STRATOCUMULUS CLOUDS BLANKETING AT LEAST
NORTHEASTERN IOWA AND POSSIBLY FURTHER SOUTHWEST INTO OUR AREA. THIS
DEPENDS ON PRECISELY WHERE THE LARGE CYCLONE SETTLES AND IF/WHEN ANY
SUBTLE REINFORCING SHORTWAVES ADVECT AROUND IT ACROSS OUR AREA. IN
ANY EVENT SIGNIFICANTLY COOLER TEMPERATURES ARE ON TAP FOR THE
WEEKEND...ALTHOUGH RAIN CHANCES ARE VERY LOW WITH JUST A FEW LIGHT
SHOWERS POSSIBLE IN THE NORTHEAST. FURTHER OUT IN THE EXTENDED
PERIODS...LONG RANGE MODELS CONTINUE TO TRY TO BRING A WAVE INTO THE
REGION ON MONDAY. GIVEN HIGH DEGREE OF UNCERTAINTY IN THIS
PATTERN...HAVE LEFT THE FORECAST BASICALLY UNCHANGED FOR MONDAY.

&&

.AVIATION...23/06Z
STILL DEALING WITH CONVECTION PERCOLATING FROM NW IA INTO CENTRAL
IA. SEEMS TO BE OCCURRING IN AREA OF WEAK TO MODERATE ELEAVTED
INSTABILITY...WEAK SURFACE CONVERGENCE AND LIFT FROM SHORTWAVE ALOFT
MOVING TOWARD THE REGION. ALL OF THESE FEATURE REMAIN IN PLAY FOR
SEVERAL MORE HOURS...SO WILL CARRY VCSH AND CB AT KFOD AND KDSM.
LATER TONIGHT...MVFR FOG IS A POSSIBILITY AND GENERALLY FOLLOWED
MODEL GUIDANCE FOR SITES WITH THE GREATEST PROBABILITY. AFT ANY FOG
BURNS OFF BY 14-15Z...VFR AND LIGHT WIND CONDITIONS EXPECTED THRU
THE END OF THE FORECAST.

&&

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

&&

SHORT TERM...MS JUL 09
LONG TERM...LEE
AVIATION...MOYER

Hazardous weather outlook, Jul 22, 9:25 PM CST, 6 hours 35 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE DES MOINES IA
1025 PM CDT WED JUL 22 2009

IAZ004>007-015>017-023>026-033>036-044>046-240330-
EMMET-KOSSUTH-WINNEBAGO-WORTH-PALO ALTO-HANCOCK-CERRO GORDO-
POCAHONTAS-HUMBOLDT-WRIGHT-FRANKLIN-SAC-CALHOUN-WEBSTER-HAMILTON-
CRAWFORD-CARROLL-GREENE-
1025 PM CDT WED JUL 22 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

A FEW THUNDERSTORMS ARE POSSIBLE OVERNIGHT. THE THREAT OF
SEVERE WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A FEW THUNDERSTORMS ARE POSSIBLE THURSDAY AFTERNOON AND
EVENING...MAINLY NORTHEAST OF A LINE THROUGH ESTHERVILLE AND WEBSTER
CITY. THE THREAT OF SEVERE WEATHER IS LOW.

SEVERE WEATHER IS POSSIBLE FRIDAY EVENING AND FRIDAY NIGHT AS A
COLD FRONT SLIDES SOUTHEAST. IF SEVERE WEATHER DOES DEVELOP...THEN
THE PRIMARY THREATS WOULD BE DAMAGING WINDS AND LARGE HAIL. THIS
SEVERE WEATHER THREAT IS NOT CERTAIN...AND DEPENDS ON FACTORS
INCLUDING THE AMOUNT OF DAYTIME HEATING AND HUMIDITY. HIGHER
DAYTIME HEATING AND HUMIDITY WOULD INCREASE THE THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

IAZ027-028-037>039-047>050-057>062-070>075-081>086-092>097-240330-
BUTLER-BREMER-HARDIN-GRUNDY-BLACK HAWK-BOONE-STORY-MARSHALL-TAMA-
AUDUBON-GUTHRIE-DALLAS-POLK-JASPER-POWESHIEK-CASS-ADAIR-MADISON-
WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-MONROE-WAPELLO-TAYLOR-
RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS-
1025 PM CDT WED JUL 22 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA.

.DAY ONE...TONIGHT

A FEW THUNDERSTORMS ARE POSSIBLE OVERNIGHT. THE THREAT OF
SEVERE WEATHER IS LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A FEW THUNDERSTORMS ARE POSSIBLE THURSDAY AFTERNOON AND
EVENING...MAINLY NORTHEAST OF A LINE THROUGH WEBSTER CITY AND
OSKALOOSA. THUNDERSTORM CHANCES WILL INCREASE FROM FRIDAY INTO
EARLY SATURDAY. THE THREAT OF SEVERE WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED THIS EVENING.

MOYER

The radar

The Des Moines radar (KDMX), 86 km away, was scanning. The volume nearest the first event began at 09:58 UTC.

Open the radar archive at this moment

Event by event

3 hail, 1 heavy rain. Local standard time, as filed.

Heavy Rain, Lucas

When: July 23, 4:00 AM CST to 4:22 AM CST
Where: Lucas County, 0.52 mi E of Chariton
Reported by: Trained Spotter
Coordinates: 41.020, -93.310

Two inches of rain fell in a short time causing smaller creeks to rise to bankfull.

Hail, Lucas

When: July 23, 4:22 AM CST
Where: Lucas County, 0.52 mi E of Chariton
Measured: 0.75 in hail
Crop damage: $5,000
Reported by: Trained Spotter
Coordinates: 41.020, -93.310

Hail, Appanoose

When: July 23, 5:00 AM CST
Where: Appanoose County, 3.76 mi WNW of Griffinsville
Measured: 1 in hail
Property damage: $5,000
Crop damage: $50,000
Reported by: Trained Spotter
Coordinates: 40.860, -93.080

A three quarter mile wide hail swath was reported that destroyed crops and damaged a pickup truck. Hail was still on the ground 8 hours after the event.

Hail, Appanoose

When: July 23, 5:08 AM CST
Where: Appanoose County, 0.52 mi W of Griffinsville
Measured: 1 in hail
Property damage: $1,000
Crop damage: $5,000
Reported by: Public
Coordinates: 40.830, -93.030

What these are

Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Iowa in 2009 Every state in 2009 This day in weather history Warnings in Iowa, July 2009

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 174173, 174172, 174171, 174170.