This drought carried over from July when record setting heat and dryness brought increasingly worse drought conditions to the region into and beyond August. Rainfall which was already deficient for the season going into July, continued much below normal in July.
Every event with a place to put it; 8 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The episode as NWS OAX wrote it up.
This drought carried over from July when record setting heat and dryness brought increasingly worse drought conditions to the region into and beyond August. Rainfall which was already deficient for the season going into July, continued much below normal in July. Although rainfall in August was spotty over southwest Iowa, many locations saw 3 to over 6 inches which helped keep the drought from intensifying too much. High temperatures consistently rose above 95 degrees during the first and last weeks of August with some sites recording a few days above 100. The middle part of the month saw temperatures dip well below normal, thus many average temperatures for August ended up close to normal. The persistent hot and dry weather kept many rivers at very low flows and also caused some local wells to become dry or go to very low flow rates. The low river levels and irrigation pressure from underground water sources also caused some municipalities to institute voluntary or mandatory water restrictions. According to the U.S. Drought Monitor, drought intensities in southwest Iowa started August in the Severe category and finished the month mostly in the Extreme category. The exception was far southwest Iowa which remained in the Severe category due to some of the heavier rain totals observed there. The drought in Iowa and surrounding states caused some crop prices, especially corn and soybeans, to reach record or near record levels in July with high prices continuing into August. According to the USDA, a little over 50 percent of the corn crop and 36 percent of the soybean crop was considered poor or very poor in Iowa by the end of August. The drought continued into September.
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 Omaha, NE wrote its last area forecast discussion before the first event at Jul 31, 10:51 PM CST, 1 hour 9 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 1151 PM CDT TUE JUL 31 2012 .AVIATION... 06Z TAFS FOR KOMA...KLNK AND KOFK. VFR CONDITIONS WILL CONTINUE...HOWEVER A FEW MID CLOUDS AND CONSIDERABLE HIGH CLOUDS WILL CONTINUE TO STREAM EASTWARD FROM CONVECTION TO OUR WEST OVERNIGHT. CLOUDS WILL INCREASE LATE WEDNESDAY AFTERNOON AND OVERNIGHT AS CONVECTION DEVELOPS TO THE WEST AND NORTH AND SPREADS SOUTHEASTWARD. INCLUDED A PROB30 AFT 01Z AT KOFK...HOWEVER HOW QUICKLY THE STORMS SPREAD SOUTHEAST IS STILL QUESTIONABLE. WILL WAIT FOR NOW TO INCLUDE TSRA MENTION AT KOMA AND KLNK AS IT MAY HOLD OFF UNTIL AFTER 06Z...BUT THIS WILL NEED TO BE MONITORED. && .PREV DISCUSSION... /ISSUED 1012 PM CDT TUE JUL 31 2012/ UPDATE... STILL QUIET TONIGHT...SO ONLY MINOR UPDATES TO THE EVENING FORECAST. DISCUSSION... THE RADAR MOSAIC HAS BECOME A LITTLE MORE ACTIVE OVER THE WESTERN HIGH PLAINS THIS EVENING...HOWEVER PRECIPITATION HAS BEEN ISOLATED. STORMS WILL CONTINUE OVER PARTS OF WEST CENTRAL NEBRASKA AND WEST CENTRAL KANSAS AND SHOULD REMAIN TO THE WEST OVERNIGHT. 00Z MODELS CONTINUE TO SHOW HOT CONDITIONS AHEAD OF THE FRONT WEDNESDAY AND SCATTERED CONVECTION DEVELOPING IN WESTERN NEBRASKA AND SOUTH DAKOTA DURING THE AFTERNOON...SPREADING SOUTHEAST OVERNIGHT. && PREV DISCUSSION... /ISSUED 250 PM CDT TUE JUL 31 2012/ DISCUSSION... HOT TEMPERATURES LOOK TO CONTINUE THROUGH THE SHORT TERM BUT SOME CHANCE OF RAIN FOR THE AREA WEDNESDAY NIGHT AND EARLY THURSDAY. HIGH PRESSURE WAS CENTERED OVER THE UPPER MIDWEST AT 19Z WITH A SURFACE TROUGH MOVING INTO THE WESTERN DAKOTAS. THE TROUGH WILL SLIDE SLOWLY SOUTH TONIGHT AND WEDNESDAY AND IS EXPECTED TO REACH THE NORTHERN NEBRASKA BORDER BY WEDNESDAY NIGHT. THIS BOUNDARY COUPLED WITH SOME WEAK UPPER WAVES WILL BRING A CHANCE OF THUNDERSTORMS TO THE AREA FOR WEDNESDAY NIGHT INTO THURSDAY MORNING BEFORE WASHING OUT. A STRONG COLD FRONT AND UPPER WAVE MOVE INTO THE NORTHERN PLAINS ON FRIDAY WHICH SHOULD ALLOW TEMPERATURES TO REACH AROUND 100 ONCE AGAIN ACROSS PARTS OF THE AREA AHEAD OF THE FRONT. IN THE EXTENDED PERIOD...BOTH THE GFS AND EURO MOVE THE COLD FRONT ACROSS THE AREA FRIDAY NIGHT REACHING THE SOUTHEAST CORNER OF NEBRASKA BY SATURDAY MORNING. THIS WILL PROVIDE ANOTHER CHANCE OF RAIN FOR THE AREA...MAINLY BEHIND THE FRONT...THROUGH SATURDAY MORNING. TEMPERATURES WILL ALSO BE COOLER OVER THE WEEKEND BEHIND THE FRONT. RELIEF LOOKS TO BE SHORT LIVED HOWEVER WITH BROAD RIDGING DEVELOPING AGAIN OVER THE CENTRAL PART OF THE COUNTRY EARLY NEXT WEEK. FOBERT && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && ZAPOTOCNY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 520 PM CDT TUE JUL 31 2012 NEZ011-012-016>018-030-031-011230- KNOX-CEDAR-ANTELOPE-PIERCE-WAYNE-BOONE-MADISON- 520 PM CDT TUE JUL 31 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST NEBRASKA. .DAY ONE...TONIGHT AND WEDNESDAY ISOLATED THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY AFTERNOON IN NORTHEAST NEBRASKA. ALTHOUGH ORGANIZED SEVERE WEATHER IS NOT EXPECTED...ISOLATED SEVERE WIND GUSTS MAY DEVELOP. TEMPERATURES ARE FORECAST TO HEAT UP TO NEAR 100 DEGREES WEDNESDAY AFTERNOON AND A COLD FRONT WILL MOVE TOWARD NORTHEAST NEBRASKA WHICH WILL PROMOTE ISOLATED THUNDERSTORM DEVELOPMENT. MORE ORGANIZED STORMS SHOULD MOVE IN LATER WEDNESDAY NIGHT. .DAYS TWO THROUGH SEVEN...WEDNESDAY NIGHT THROUGH TUESDAY SCATTERED THUNDERSTORMS ARE FORECAST WEDNESDAY NIGHT THROUGH THURSDAY MORNING WITH MORE STORMS THURSDAY NIGHT THROUGH SATURDAY. SOME OF THE STORMS MAY BE SEVERE WITH DAMAGING WINDS AND LARGE HAIL. THE STORMS ARE THE RESULT OF A COUPLE OF WEATHER DISTURBANCES MOVING THROUGH THE NORTHERN PLAINS THAT DRAG A FRONTAL BOUNDARY INTO THE OUTLOOK AREA WITH EACH DISTURBANCE. TEMPERATURES HEAT UP AHEAD OF THE FRONT AND MONSOONAL MOISTURE POOLS ALONG THE FRONT WITH SCATTERED THUNDERSTORM DEVELOPMENT ALONG AND BEHIND THE FRONT. THE WIND PATTERN ALOFT FAVORS DAMAGING WINDS AND LARGE HAIL COULD ALSO ACCOMPANY THE STRONGER STORMS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT BUT MAY BE NEEDED LATE WEDNESDAY AND WEDNESDAY NIGHT. IAZ043-055-056-069-079-080-090-091-NEZ015-032>034-042>045-050>053- 065>068-078-088>093-011230- MONONA-HARRISON-SHELBY-POTTAWATTAMIE-MILLS-MONTGOMERY-FREMONT- PAGE-THURSTON-STANTON-CUMING-BURT-PLATTE-COLFAX-DODGE-WASHINGTON- BUTLER-SAUNDERS-DOUGLAS-SARPY-SEWARD-LANCASTER-CASS-OTOE-SALINE- JEFFERSON-GAGE-JOHNSON-NEMAHA-PAWNEE-RICHARDSON- 520 PM CDT TUE JUL 31 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST IOWA...WEST CENTRAL IOWA...EAST CENTRAL NEBRASKA...NORTHEAST NEBRASKA AND SOUTHEAST NEBRASKA. .DAY ONE...TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...WEDNESDAY NIGHT THROUGH TUESDAY SCATTERED THUNDERSTORMS ARE FORECAST WEDNESDAY NIGHT THROUGH THURSDAY MORNING WITH MORE STORMS THURSDAY NIGHT THROUGH SATURDAY. SOME OF THE STORMS MAY BE SEVERE WITH DAMAGING WINDS AND LARGE HAIL. THE STORMS ARE THE RESULT OF A COUPLE OF WEATHER DISTURBANCES MOVING THROUGH THE NORTHERN PLAINS THAT DRAG A FRONTAL BOUNDARY INTO THE OUTLOOK AREA WITH EACH DISTURBANCE. TEMPERATURES HEAT UP AHEAD OF THE FRONT AND MONSOONAL MOISTURE POOLS ALONG THE FRONT WITH SCATTERED THUNDERSTORM DEVELOPMENT ALONG AND BEHIND THE FRONT. THE WIND PATTERN ALOFT FAVORS DAMAGING WINDS AND LARGE HAIL COULD ALSO ACCOMPANY THE STRONGER STORMS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT OR WEDNESDAY...BUT MAY BE NEEDED WEDNESDAY NIGHT. ZAPOTOCNY
The national radar mosaic for the moment the first event began.
8 drought. Local standard time, as filed.
Drought conditions caused the county to continue a burn ban which started in mid July and carried over into September.
Drought conditions caused the county to continue a burn ban which started in mid July and carried over into September.
Drought conditions caused the county to continue a burn ban which started in mid July and carried over into September.
Drought conditions caused the county to continue a burn ban which started in mid July and carried over into September.
Drought conditions caused the county to continue a burn ban which started in mid July and carried over into September.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2012Every state in 2012This day in weather historyWarnings in Iowa, August 2012
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: 399146, 399147, 399148, 399149, 399150, 399151, 399152, 399153.