RSS FeedsHydrologic Summary for September 2004 for the Area Served by the NWS Forecast Office at Sioux Falls, SD
Summary
September saw very hot and very wet conditions across the entire region.
Flooding
There was one major flash flood event in September. Much of northwest Iowa received extremely heavy rainfall on the 14th, which resulted in significant flash flooding and urban flooding in several counties. Runoff from these rains, and additional rains over the next several days in the same area, resulted in moderate flooding on the Ocheyedan and Little Sioux rivers in northwest Iowa. The gage at Linn Grove recorded the second highest stage on record, and Spencer and Cherokee saw stages that ranked in the top 7 to 14 on record. Please see the table at the bottom of this report for more details on the river flooding in September.
General Hydrologic Information
Temperatures in September were much above normal across the region. Average temperatures for the month were generally 4 to 6 degrees above the 30 year average.Precipitation for the month was above normal for the entire region. Precipitation totals were generally 2 to 6 inches above normal. Spencer Iowa recorded its greatest monthly total on record with over 14 inches.
Soil Moisture conditions at the end of September were near normal in the southern parts of the region, with surpluses of 1 to 2 inches across the north. The National Drought Monitor indicated abnormally dry conditions persisting in the extreme western areas, with near normal conditions across the rest of the region.
Mike Gillispie
October 14, 2004
October 14, 2004
NWS FORM E-3 U.S. DEPARTMENT OF COMMERCE River District:
NOAA/ NATIONAL WEATHER SERVICE WFO SIOUX FALLS
FLOOD STAGE REPORT Report for:
SEPTEMBER 2004
RIVER/STATION FLOOD ABOVE FLOOD STAGE CREST
STAGE FROM-TO STAGE DATE
LITTLE SIOUX RIVER
SPWI4 10.0 9/15-9/29 14.30 9/18
LNNI4 18.0 9/16-10/2 21.12 9/19
CHKI4 17.0 9/16-9/17 19.72 9/16
9/18-9/20 19.10 9/19
OCHEYEDAN RIVER
SPOI4 8.0 9/15-9/17 9.67 9/16
9/17-9/20 9.95 9/19
