WINTER 2006 BASIN CONDITIONS
March 08, 2006
HUDSON BAY DRAINAGE
Red River of the North River Basin
Fall precipitation in the headwater area exceeded 300 percent of normal and averaged 100 to 300 percent of normal over the remainder of the basin. Model simulated soil moisture was above normal in September and October due to summer precipitation. Two major storm systems tracked over the southern portion of the basin in early to mid November. Due to the temperature regime during these events, the precipitation fell as a liquid, liquid snow mix. This resulted in a ground ice layer of 1 to 2 inches, which currently still exists below the snow cover in southeast North Dakota and south of Fargo to the headwater area in Minnesota. In the Red Lake River Basin, field reports from the past few days indicate a ground level ice layer of 1.0 to 1.5 inches below the snow pack.
Currently, streamflows over much of the Red River Basin are above normal according to the USGS. River ice thickness ranges from 9 to 18 inches which is about a foot less than normal. Ice thickness on many streams was classified as "unsafe" to walk on at several locations. Frost reports indicate little to no frost existed in the basin upstream of Halstad into January. February temperatures were below normal. Snow water equivalent observations for most of the Valley currently range from 3.0 to 4.5 inches. The model simulated soil moisture and the continuation of above normal base flows indicate very wet soils over most of the basin. The only exception is the Sheyenne River Basin where the snow water equivalent reports are from 1 to 3 inches. In the Canadian portion of the Pembina River Basin, reports indicate soil moisture last fall was 125 to 130 percent of normal. Several snow events during February and early March have added as much as an additional 10 inches to the existing snow pack. In the headwaters of the Little Pembina River, cooperative observers have reported in excess of 5.0 inches of snow water equivalent. The three largest reservoirs are undergoing winter draw down operations. Orwell Reservoir on the Ottertail River is currently discharging near 1000 cfs while Lake Traverse-White Rock Reservoir is discharging 900 cfs to make room for expected snow melt. Baldhill Reservoir on the Sheyenne River is at the selected drawdown elevation and discharging about 250 cfs to maintain the current pool elevation.
Significant river flooding is expected along the Red River of the North
and some of its tributaries this spring.
For more detail visit the Grand Forks, ND Weather Forecast Office Website.
Devils Lake Basin
The late summer precipitation over the southern portion of the basin was 4.0 to 5.0 inches above normal. Precipitation since early fall over the same area has been nearly 4.0 inches below normal. In the northern portion of the basin, the fall precipitation was above normal, mainly due to a early October snow event. Fall inflow was much below normal allowing the lake level to drop three quarters of a foot since early September, 2005. Approximately, 100 cfs has continued to flow between Devils Lake and Stump Lake during most of the winter months. Ice thickness is below normal near the City of Devils Lake measuring 15 inches, while other locations report 24.0 inches of ice. Modeled snow water equivalent currently ranges from 1.0 to 3.0 inches over the basin, and the modeled soil moisture shows the basin close to saturation. Field observations indicate that only thin and slush ice has formed on Stump Lake.
Souris River Basin
Both the Canadian and the US portions of the Souris River Basin received less than 50 percent of normal precipitation during the fall of 2005. River flows during the fall period were 25 to 75 percent of normal. The current levels at Rafferty and Alameda Reservoirs, located in Saskatchewan are slightly below the desired elevation and no releases are planned for this coming spring. Lake Darling has 15 to 18 inches of ice in mid February, and according to the USGS staff there are many locations on the Souris that are ice free.
Current frost depth in the Minot area is 20 inches and 12.0 to 14.0 inches in the Rolette area. The basin is nearly snow-free with the exception of the lower portion from Towner to Westhope, ND. The greatest snowpack and water equivalent exists in the Turtle Mountains and areas to the east. Snow water equivalent in this area averages about 3.5 inches based on NOHRSC flights and model simulated water equivalent.
GREAT LAKES DRAINAGE
Eastern Wisconsin Streams
Early fall river flows were 50 to 90 percent of normal while November flows were 150 percent of normal. Rivers were generally at baseflow levels before entering freeze up. Some rivers are ice affected at this time. The Root River is ice free and the flow is currently at the 50 percentile according to the USGS. There has been no flooding for several months and only brief rises occurred on the Root River in the late fall and early winter. There is about 20 to 25 inches of snow on the ground in the far northern basins, of which up to 10 inches fell during the recent mid February snow event. Snow water equivalents are around 3.5 to 4.5 inches in the far north in the Langlade, Shawano, Morgan, and Gillett basins, but are generally less than 1 inch elsewhere. Frost depths vary from 5 to 20 inches.
Western Lake Superior
Late fall rains increased soil moisture before the cold weather season. Snow depths range from a few feet at some locations along the North Shore with lake affect snow, to 2 inches in northern Wisconsin around Bayfield. Modeled water content of the snow ranges from over 7.0 inches around the Pigeon River along the Canadian border to a few tenths f an inch around Bayfield County, Wisconsin. In the St. Louis River watershed, water content of the snow is in the 2.0 to 3.0 inch range in he upper part of the watershed and a little above 3.0 inches in the lower part of the asin. The St. Louis River at Scanlon is currently flowing at slightly less than at 50 percent of normal. The reservoirs n this watershed are being drawn down and should be able to capture the spring runoff in their respective areas.
Upper Peninsula of Michigan River Basins
Fall precipitation totals were 100 to 200 percent above normal over the basin. Fall flows were normal. Lake effect snows have contributed the greatest snow accumulations along the coastal area and into the easternUpper Peninsula. Amounts of 6.0 inches of snow water equivalent are typical due to lake affect snow in the Marquette area. The interior snowwater equivalent conditions are roughly 3.0 to 4.0 inches. Frost depths are estimated to be shallow due to the warm winter temperatures.
Menominee River Basin
Last summer the Menominee River Basin only received 50 to 75 percent of normal precipitation so going into October flows were well below normal. However, precipitation during the fall recharged the soils and baseflow levels to near normal conditions. Recent snow surveys indicate 2.0 to 3.0 inches of snow water equivalent over the southern end of the basin and 3.5 to 4.0 inches in the upper portion of the basinabove the two largest reservoirs, Way Dam and Peavy Falls Dam. Way Dam has completed it's draw down and Peavy Falls Dam will now begin it'swinter draw down. River levels on the Menominee River near Pembine WI have been periodically elevated during the last couple months due to changing ice conditions, but has remained below flood stage.
The stage record during the past couple weeks seems to indicate that there is a river ice cover downstream of the gage, but no ice jam problems are anticipated at this time. Temperatures have remained generally below freezing so little or no melt has occurred.
Northern Lower Michigan Basins
Precipitation totals were 150 to 300 percent of normal over the basin for November and December. River flows were below normal during September and October and near normal the remainder of the fall according to the USGS. Current snow water equivalent is 1.0 to 2.0 inches in the southern portion of the basin and 2.0 to 4.0 inches in the northern portion of the basin. Frost depths are estimated to be shallow due to the warm winter temperatures. This lack of frost has allowed the snow pack to percolate and keep soil states fairly wet.
Grand, Kalamazoo, St. Joseph, Saginaw and White River Basins
Fall soil moisture ranged from dry in eastern portions of the basin to moderate drought levels over the western half according to the U.S. Drought Monitor in November. Fall flows ranged from 10 to 75 percent of normal in September and October to near normal during the rest of the season. However a major storm in early November and a series of smaller storms during the winter months has increased soil moisture conditions significantly. River flow levels in early winter were above normal according to the USGS. Over the past several weeks the flows have been declining to the current rates that average 60 to 80 percent of normal. No significant flooding occurred during the winter. Frost depths are being reported as very shallow. As the result of two snowstorms the past 10 days, snow depths have increased across the Saginaw and White River Basins. Snow depths range from 4 to 10 inches over the Tittabawassee and Tobacco River basins. Little or no snow cover remains over the Kalamazoo and St Joseph basins. In the Grand River Basin, snow cover is now limited to the Muskegon River basin.
Southeastern Michigan Streams
September and October flows were below normal according to the USGS and near normal to above normal in late fall. Fall precipitation was 100 to 300 percent of normal during November and December which resulted in minor to moderate within bank rises, but no flooding occurred. The simulated model states were affected by the previously mentioned wet episodes and are therefore fairly sensitive to precipitation. Over the past several weeks, there have been a few moderate to bankfull rises from a combined rain/snowmelt event. Currently, river flows are above normal, in the 70 to 90 percentile range, according to the USGS. Little or no ice has been reported in the rivers. The northern basins had 1 to 6inches of snow depth with about a half inch of snow water content. There is little or no snow in the southern basins.
UPPER MISSISSIPPI RIVER DRAINAGE
Minnesota Tributaries to the Mississippi River
Minnesota River Basin
Soils remain very wet across the basin as a result of above normal late summer and fall precipitation. August through December precipitation ranked from 150 to 200 percent of normal over the basin. The Standardized Precipitation Index categorizes conditions as very wet to extremely wet in the upper portion of the basin. Streamflow also indicates very wet conditions, with baseflow levels remaining abovethe 90th percentile. While the winter began with above normal snowfall from early season storms, the trend has reversed over last few months with lower than normal snowfall. The warm temperatures in January depleted the existing snow cover over most of the lower basin below Redwood Falls. This region currently has little to no existing snow cover, with only a few tenths of water equivalent present. In the upper basin above Redwood Falls, the snowpack increases toward the west, with the heaviest amounts above La Qui Parle reservoir. While some of the snow melted during January, there is still 2.0 to 3.0 inches of water equivalent in the upper basin. Above normal temperatures in January inhibited soil frost development during the first half of the season. Some frost has redeveloped with the recent cooler temperature trend. Frost depths of 12 to 18 inches are now present in the basin, which remains well below normal. At this point of the season frost should be near the maximum depth for the year.
Wisconsin Tributaries to the Mississippi River
Chippewa River Basin
October and November precipitation was about 125 percent of normal. River flows were normal during most of the fall over the Chippewa basin. Currently, most of the basin has snow cover and the snow water equivalents range from a quarter of an inch south to around 3 inches in the north. Frost depths are shallow over most of the basin. Current model states indicate the upper soil levels are saturated over the entire basin.
Wisconsin River Basin
The US Drought Monitor showed the headwaters and the lower end of the Wisconsin River basin to be abnormally dry until the end of January. River flow at Muscoda, Wisconsin is currently between the 50 percent of normal and 80 percent of normal. The current modeled soil moisture remains in the average to above average category. Current snow depths in the basin range from 25 inches in the headwaters to zero at Muscoda, with snow water contents ranging from 3.0 to 4.0 inches in the headwaters to 2.0 inches in the central part of the basin to zero at Muscoda. Most of the reservoirs on the Wisconsin River are being drawn down at this time. Smaller rivers have modeled soil moisture states that are average to above average for this time of year, but little snow is available in these basins. The Trempeleau River is currently running at a 50 percent of normal, while the Black River is currently at an 80 percent of normal and the La Crosse River is at less than the 80 percent of normal. Most of these basins received a few inches of snow over the past couple weeks.
Iowa Tributaries to the Mississippi River
Skunk, Wapsipinicon, Maquoketa,Cedar and Iowa River Basins
Streamflow during the Fall in these river basins was normal and that condition continued into early 2006. Precipitation was 50 percent of normal during September, but generally rebounded to the normal range for November and December. There is currently no ice cover on streams and no frost is being reported. Coralville Reservoir is currently undergoing the winter draw down. Modeled soil moisture states are wet in the upper layer across these basins. Some holding capacity is available in the lower layer. A mid February storm deposited 1 to 5 inches of new snow over the northern reaches of these basins that has since melted. There is currently no snow reported in these river basins.
Des Moines River Basin
Precipitation during the fall was 70 to 90 percent of normal for the western portion of the basin and 50 to 70 percent for the eastern portion of the Des Moines River basin. River flows were normal during the fall according to the USGS. January precipitation 1.0 to 2.0 inches above normal. Temperatures from November to mid February were 3 to 4 degrees above normal There is currently no snow in the basin. This winters snowfall is the lowest since 1989 according to Climatology Bureau, Iowa Department of Agriculture and Land Stewardship, (IDAL). There is currently little to no frost in the Des Moines River basin. The current flow in the Raccoon River is about 20 percent of normal. At Stratford, the flow is about 250 percent of normal. The simulated model states indicate the the upper zone of soil moisture is 90 percent of capacity and lower zone is 30 to 50 percent of capacity.
Illinois Tributaries to the Mississippi River
Rock River Basin
During the fall, the ongoing drought conditions continued in northern Illinois and southern Wisconsin. River flows were 10 to 25 percent of normal. Fall rainfall was only 10 to 50 percent of normal. Late 2005 river flows were 10 to 25 percent of normal, which was reflected by the lack of precipitation. January temperatures were unseasonably warm and precipitation was 150 percent of normal, (as shown above in the Illinois River Basin discussion) relieving some of the drought conditions temporarily. A few minor ice jams occurred in January in the Rock River, but no flooding was reported. Frost depths have been less than 1 foot
and currently 6 inches or less is common across the basin. A mid February storm event provided up to 10 inches of snow in the northern portion of the basin, of which only a few inches currently remain.
Kaskaskia and Big Muddy River Basins
Fall precipitation was 25 to 50 percent of normal during October and December and 150 percent of normal in November. Fall river flows were normal according to the USGS. Precipitation for January was near normal. While recent rainfall has increased soil moisture in the upper layers, the deep soil moisture contents are near normal for this time of year. Currently, no snow or frost exists in the basin. Streamflow levels are currently near seasonal normals on the Big Muddy to a little below normal on the Kaskaskia River.
Illinois River basin
Summer 2005 conditions over the Illinois River Basin continued through the fall months. Soil conditions were dry throughout the basin. River flows continued to be 25 percent of normal. The precipitation totals were low except for November when precipitation was 110 percent of normal. Precipitation totals in Illinois during January were above normal across the state. This created near-surface soil moisture conditions that were close to normal statewide according to the Illinois State Water Survey (ISWS). Currently, soils are generally very wet as indicated by the model states, even though basin flows are classified as below normal for the 7-day average streamflow by the USGS. The wettest areas are the Calumet, Fox, Des Plaines and Kankakee River Basins. At the current time, there is little or no snow within the southern two thirds of the Illinois River Basin. There is no reported frost at this time. About 8 to 12 inches of new snow was reported in the Fox River Basin as a result of the mid February snow storm, but there is little or no snow within the Illinois River basin at this time.
Missouri Tributaries to the Mississippi River
Meramec River River Basin
Last fall, river flows were near normal according to the USGS. Precipitation was 100 to 200 percent of normal in September and November and 50 percent of normal in October and December. Currently the Meramec River flows are normal while soil moisture conditions are fairly saturated due to recent rain events. There is currently no snow cover or frost in the Meramec River basin.
Fabius, Fox, Salt, and Cuivre River Basins
The northeast Missouri tributaries entered the winter season with drier than normal antecedent conditions. The trend continued in November and December with below normal precipitation. Minor re-charge occurred with above normal precipitation in January...but at mid February the rivers were at low baseflow with flows ranking below the 25th percentile. Due to the low flows, occasional channel freeze-overs have been noted at some gage locations. There was no snow in the basin at mid February. However, spring flooding in northeast Missouri typically occurs from short duration intense rainfall and fast runoff events.
Mississippi River Mainstem
Mississippi River from the Headwater Area to Red Wing, MN
During the summer of 2005, precipitation was normal throughout the basin. However, fall precipitation was 125 percent in the north and southeast, but as high as 200 percent of normal across the central portion of the basin including the Crow River, Elk River, Rum River, Sauk River, and the Crow Wing River. Frost depths throughout the basin are about a foot or less, which is about a foot shallower than last year. Also, there are no reports of ice layers in the snowpack at this time. Model simulated water equivalents range from about a quarter of an inch in the Cannon Basin in the south to about 2.5 to 3.0 inches in the Crow
Wing Basin in the northwest. These simulated amounts are below average compared to simulated averages for the last 50 years. As a result of the wet fall, some midwinter snowmelt, and a shallow frost, flows are above normal for this time of year. Except for a slight moisture deficit in the headwaters area, modeled soil moisture states are quite wet. Since mid February, up to a half inch of new water equivalent fell over the headwaters area of the Mississippi River watershed bringing the current total to near 4.0 inches.
There have been several ice jams this winter on the Mississippi River at Fort Ripley, Minneapolis, and Anoka and on the Sauk River at St. Cloud. These have been mainly freeze-up ice jams which occurred earlier in the winter, but have dissipated during the relatively warm month of January. Recent cold temperatures have been affecting river levels slightly, but with a relatively degraded ice cover this late in the season, ice jams this spring are not a big concern in this basin. The headwaters reservoirs are still holding steady at about a half foot above their normal drawdown level for the winter because of a below normal snowpack in these basins.
Mississippi River from Lake City, MN to Lock/Dam 10 at Guttenberg, IA
Precipitation was 100 to 125 percent of normal in November 2005, creating wet antecedent conditions going into the winter months. Since then, precipitation has been about 50 percent normal. Deep soil moisture is a little below normal...especially over the northeast Iowa portion of the basin. Snowfall has been about 1 foot below normal. The early snowpack melted and by early February snow was almost non-existent. Frost depths are shallow and much of the mid-winter snowmelt runoff has moved into the upper soil layers. On the mainstem Mississippi, only L/D 10 was reporting 100 percent ice cover in the pool. Lake Pepin ice thickness is about half of typically observed. River ice jams have been minimal. Faster flowing tributaries have experienced some shore ice and only a few tributary gages were showing signs of minor backwater from ice. Streamflows at mid February were about double the longterm median on both the tribuaries and the mainstem Mississippi River due to the wet upper zones draining.
A snowstorm in mid February dropped 4 to 8 inches of snow over southeastern Minnesota but the snow was dry with liquid equivalents less than half an inch. A brief cold snap caused minor ice formation on some tributaries, but more significantly ice formation on the mainstem Mississippi River briefly cut back flows nearly 50 percent at L/D 10. With moderating temperatures, by the beginning of March the river flows had rebounded to near previous levels and snow was mostly non-existent in the basin.
Mississippi River from Lock/Dam 11 at Dubuque, IA to Dam 22 at Saverton, MO
Drought conditions were prevalent in this reach of the Mississippi last summer and fall. November was the only month reporting above normal precipitation of 100 to 125 percent. River flows were normal during the fall and continue to be normal at the present time according to the USGS. Ground frost in the far northern portion varies from 2 to 8 inches based on only a few reports and no ground frost being reported in the southern portion of the basin. There currently is no snow cover. Due to warm weather during in late February, all ice was lost on the Mississippi River from Dam 14 south. Ice is still being reported, mainly in the pools, from Dam 13 northward, but it has deteriorated somewhat over the past two weeks.
Mississippi River from Louisiana to Chester, IL
Fall flows on this reach of the Mississippi were classified as normal according to the USGS. Precipitation was 10 to 50 of normal during October and December and normal during November. River levels and flows have been slightly higher than normal since winter began with the exception of a 2-3 week bitterly cold period in February when levels dropped several feet in the St. Louis area. There currently is little to no snow cover and no ground frost being reported.