The National Weather Service has been issuing Hydrologic Outlooks for the Missouri River in the Bismarck/Mandan area for the past few weeks. These Hydrologic Outlooks are intended to give the public a little extra awareness of the potential for seeing the Missouri River ice over during colder weather. As ice accumulates on the river the expectation is that the river would undergo a fairly rapid rise from its currently low water levels, to something that is 4-7 feet higher than present. Last year saw a rise in the river on the upper extreme of these expectations as ice accumulated in the sharp bend of the river near the University of Mary. Ice affected flow is generally not predictable as there are too many variables, but the conditions that lead to a freezing over of the river are and it is during these times that the NWS would like to encourage people to remain aware of the potential for rapid changes in the water level of the river.
Below is the latest example of the Hydrologic Outlooks being issued by the NWS, the NWS will continue to issue this product as needed until the river stabilizes under its winter time ice cover.
NATIONAL WEATHER SERVICE BISMARCK ND
1127 AM CST TUE DEC 18 2012
...LIKELIHOOD OF MISSOURI RIVER GAINING ICE...
THE WATER TEMPERATURE OF THE MISSOURI RIVER AT BISMARCK HAS
HOVERED BETWEEN 33.5 AND 34.5 DEGREES FOR THE PAST FEW
DAYS. THIS TEMPERATURE RANGE HAS NOT ALLOWED THE FORMATION OF ICE
COVER ON MUCH OF THE RIVER. DESPITE MUCH COOLER TEMPERATURES FOR
WEDNESDAY AND THURSDAY WITH HIGHS IN THE TEENS AND LOWS AROUND 2
TO 4 DEGREES...NOT MUCH ICE FORMATION SHOULD BE EXPECTED BEFORE
TEMPERATURES RETURN TO THE MID 20S ON FRIDAY. HOWEVER...AFTER
FRIDAY A LONGER DURATION OF COLDER WEATHER WITH FORECAST HIGHS IN
THE TEENS AND LOWS NEAR ZERO WILL LIKELY RESULT IN THE FORMATION
OF ICE ON THE MISSOURI RIVER.
ALTHOUGH DIFFICULT TO FORECAST...FORMATION OF SIGNIFICANT ICE
COVER IN THE BISMARCK MANDAN AREA DOES APPEAR LIKELY SOME TIME
AROUND CHRISTMAS DAY. ICING OVER OF THE RIVER NORMALLY INCREASES
WATER LEVELS BY 4 TO 7 FEET. PEOPLE WHO OBSERVE WHAT THEY BELIEVE
TO BE EXCESSIVE RISES...OR PROBLEMATIC HIGH WATER...ASSOCIATED
WITH THE RIVER ARE ENCOURAGED TO REPORT THOSE OBSERVATIONS TO
THEIR LOCAL EMERGENCY MANAGEMENT FOR RELAY TO THE NATIONAL WEATHER
THIS OUTLOOK WILL BE UPDATED NO LATER THAN FRIDAY DECEMBER 21.