Year End Summary for 2021
YEAR END SUMMARY STATION NAME: Poplar River nr Lutsen, 0.2mi US of MN61 STATION NUMBER: H01063003 YEAR: 2021 PREPARED BY: Jonathan Libbey, jonathan.libbey@state.mn.us CLIMATE SUMMARY: Division 3, 2021: After a generally mild winter with below-normal snowfall, warm and dry conditions dominated the May-through-October liquid precipitation season, leading to widespread Extreme drought categorizations on the US Drought Monitor. Precipitation from May through October averaged about 63% of normal. May through July was the driest on record back to 1895, with an average of under 5.0 inches of rain falling over the 3-month period (normal would have been over 11 inches). June and July had bouts of extreme heat, which worsened the drought conditions, and May through October averaged over 4.0 degrees F above normal and was the warmest on record. Normal and above-normal precipitation during late summer and autumn helped drought conditions improve, although deficits remained. No significant precipitation events occurred. Mean temperatures fell below freezing in early November, and the seasonal snow pack formed during mid-November in far northern areas, and by early December elsewhere. STATION OPERATION SUMMARY: Is this site monitored year round? Yes Open water dates - estimated Ice out and Ice in: Ice out 4/7/21, ice in 11/18/21. Period of data record (if different from ice out/ice in dates): 1/1/21 to 12/31/21. Summary of equipment - related factors that impacted data collection: Equipment performed well during open water. During winter there were a lot of level spikes from cold temps or ice that had to be deleted. Daily discharges were estimated during these periods. DISCHARGE SUMMARY: Number of flow measurements for monitoring season: 8 Was the full range of flows measured for the season? No, moderate and low flows were captured but high flows and very low flows were not. Highest measurement was 180cfs, highest computed discharge was 720cfs for 25%. Lowest measurement was 8.73cfs, lowest computed discharge was 1.45cfs. Was a new rating developed? No General summary of control changes/shifts needed: Ice shifts needed in winter, moderate flow debris shifts were seen from April until Oct, and a small scour was observed in late August after a small event. Quality of computed daily discharges: Discharges coded good, fair, poor, ice, and estimated. PRECIPITATION DATA OVERVIEW: Was precipitation data collected at this site? YES Climatological liquid precipitation period: 5/1/21 to 10/31/21. Was there a complete and acceptable precipitation record for this period? No, Rain bucket was found to be under reporting during a field calibration on 8/31/21. It recorded 52/100 tips. A bad wire was replaced and it performed well the rest of the season. Data was removed from 6/9 to 8/31.