NWS Boulder Partners,
We will very soon start doing Situation Reports and conference calls at a regular cadence in preparation for the major storm potential Friday through this weekend. At this point still about ~4 days before the impacts might begin, we couldn't provide a lot of detailed information in those briefings and SitReps yet. Nevertheless, we wanted to provide you with our latest thoughts since this potential storm continues to be all over the news and on social media..
- Confidence in a significant winter storm Friday - Sunday/Monday has increased a bit since Greg Hanson last emailed you all.
- Mountains west of the Continental Divide: Light snow will likely continue off and from late this evening into this weekend, but amounts will be fairly light overall with only minor travel impacts expected.
- This storm is expected to generate deep and very moist easterly flow, which means the heaviest snow will be from the Continental Divide eastward across the foothills and the plains Friday through Sunday/Monday.
- The storm is expected to be a slow mover, and a large area of Colorado should be impacted in some fashion for 48-72 hours
- Timing: Driving conditions could deteriorate as soon as Friday evening across the eastern foothills, I-25 corridor, and eastern plains
- Saturday still looks to see the heaviest snow, but there are now indications that Sunday could also see heavy snow, and snow may continue into Monday. This means that improving conditions may not occur until Monday afternoon.
- There is still plenty of uncertainty on timing and amounts, which is the main reason why we still have not shown any snowfall total graphics for this weekend.
Bottom Line: If all the conditions come together like a fair number of computer models are indicating, we may be measuring the snowfall in feet across a significant portion of northern Colorado by the time the snow winds down sometime on Sunday or even Monday. We will begin adding more details on potential snow amounts, impacts, and timing as soon as Wednesday.
Feel free to reach out to Greg Hanson or our operations line 303-494-4479 to talk to a forecaster.
Paul Schlatter
Science and Operations Officer
National Weather Service
Denver/Boulder Weather Forecast Office