According to the NWS Medford, an Atmospheric River event is possible for our area and region beginning Saturday night. The details of this event are still uncertain but depending on the timing of the mix of cold air and moisture we could see either a significant amount of snow, rain, or a combination of both. Flooding of small streams and rivers is a possibility and we will be watching all of this close as the NWS updates us.
We will have more information about this developing weather story tomorrow as the details get worked out and we get closer to the timing of the event.
A significant amount of moisture is expected to move into the area later this weekend and last into at least early next week as two fronts impact the area while moisture streams up from tropical origins. Snow levels will be higher overall, but heavy snow is expected for the Cascades, Siskiyous, and higher elevations in western Siskiyou County. Meanwhile, heavy rain is expected along the coast, coastal mountains and lower elevations in western Siskiyou County.
Above: Forecast 72 Hour precipitation early Sunday morning through early Wednesday morning. This is subject to change and is a current estimate. The above map is a precipitation estimate and doesn’t depict areas of rain and snow.
Above: A forecast tool indicating a plume of moisture (Atmospheric River) that is expected to setup and transport moisture from the Hawaii area to Oregon and Northern California.
Right now plan on the possibility of a significant amount of precipitation in the mountains and possible flooding and travel disruptions in our region.
Additional weather warnings, watches, and alerts may be issued.
Winter Storm Watch issued February 21 at 2:29PM PST until February 25 at 10:00AM PST by NWS Medford
.A storm with a significant amount of moisture could bring moderate to heavy mountain snow to the Cascades, mountains in Western Siskiyou County, and portions of the East Side Saturday night into at least Monday morning.
…WINTER STORM WATCH IN EFFECT FROM SATURDAY EVENING THROUGH MONDAY MORNING…
* WHAT… Heavy snow possible. Total snow accumulations of 12 to 18 inches with local amounts up to 24 inches. Winds could gust as high as 45 mph in exposed areas.
* WHERE… Highway 97 and 31, including the cities of Chemult and Crescent.
* WHEN… From Saturday evening through Monday morning.
* ADDITIONAL DETAILS… Travel could be very difficult to impossible. Visibilities could be reduced by blowing snow in more exposed areas where winds are gusty.
* View the hazard area in detail at https://www.wrh.noaa.gov/mfr/HAZARD
* Stock emergency kit with tire chains, flashlight, batteries, blankets, food, water, and medications.
* The safest place during a winter storm is indoors.
* Plan now to avoid traveling during the storm.
* A Winter Storm Watch means there is potential for significant snow accumulations that may create dangerous travel.
Hydrologic Outlook ORC011-015-019-029-033-035-037-CAC049-093-232225- Hydrologic Outlook National Weather Service Medford, OR 225 PM PST Thu Feb 21 2019 ...Flood Potential Outlook for quick river rises, main stem river flooding, and the potential for snow melt flooding on rivers and streams in the following counties in California...Modoc...Siskiyou and in Oregon...Coos...Curry...Douglas...Jackson...Josephine...Klamath...Lake... .At atmospheric river will bring a good chance for periods of heavy precipitation over Coos, Curry, and Western Siskiyou Counties Sunday through Tuesday and possibly longer. A front will likely stall over the forecast area late this weekend with waves of heavier precipitation moving through. The front will push through the area by early or the middle of next week. 4 to 8 inches of rainfall are possible at the coast. Confidence is low on how much rainfall and timing of heaviest rainfall, but recent data have increased the chance for significant river rises and flooding enough to warrant this outlook. Farther east, there is higher uncertainty in terms of flooding potential. It`s unknown how far inland the heaviest precipitation will extend and for how long. However, periods of heavy precipitation are possible here as well, and given how much snowpack is in the mountains, an extended period of heavy rain on snow would result in flooding of small creeks and streams as well as significant rises on main stem rivers. A flood potential outlook is issued when there is the potential for significant rises or flooding along rivers and streams. The exact scenario for flooding remains uncertain. This product will be updated as necessary. Watches and warnings may be issued by the National Weather Service if this situation worsens.