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Published April 05, 2011, 05:16 PM

Spring Melt Outlook from NWS

The following is an update to the spring melt outlook from the National Weather Service

Changes continue to occur within the atmosphere, setting the stage for a potential stormy period over the next 5 to 15 day period. Information presented is based on data and forecasts generated by the Grand Forks NWS and the Climate Prediction Center (CPC).

Synopsis:

The blocking pattern which has kept the main storm track south of the Red River Valley region the past 10 days continues to break down, as a series of major storm systems in the Pacific move east. The Madden-Julian Oscillation (MJO), an important player in the global weather pattern, is moving into the western Pacific. It is entering a location that has the potential to produce significant impacts on our weather.

Near Term forecast: April 6 - 12

Refer to the NWS Grand Forks web page for updates. There are indications that a strong storm system will be moving out of the Rockies into the plains this weekend and early next week, April 9 - 11. Based on the latest guidance provided by the National Centers for Environmental Prediction, rain will spread into the southern Red River Valley late Saturday the 9th, with increasing chances for significant rains Sunday - Monday the 10th and 11th. Details are sketchy at this time, as recent computer guidance has struggled with these systems. Witness last weekends storm that eventually produced significant snows much farther north than was originally forecast. Stay tuned for updates.

Extended Outlook April 13 - 19

Based on information from the CPC, a trough of low pressure in the eastern Pacific will be moving inland, as high pressure over the southeast U.S. weakens. The result will be a broad southwest flow in the atmosphere into mid month that will maintain the threat for mid-west or northern plains storms before a drier pattern develops. Extended range computer guidance and the climatology of MJO events suggests another significant storm in the April 16 -19 time period.

On balance there is little chance for prolonged freezing temperatures that would impact the current or future melt cycle. Essentially, the melt cycle will continue with little slow down expected.

At this time it is impossible to make Quantitative Precipitation Forecasts beyond about day 5, therefore we refer to the three categories of below, near normal or above to describe the precipitation threat. The overall pattern should continue transitioning to the above normal precipitation category into the second week of April as described above. It is important to remember that April is a transition period, when weather systems can develop and intensity rapidly. Due to the technological limitations, the NWS in Grand Forks can only relay trends of major storm systems beyond the 7 to 10 day period.

As the overall pattern transitions to a more stormy pattern, your NWS will update this Hazards Outlook.

Mark Ewens

Climate Services Focal Point

NWS Grand Forks

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