Potential Weekend Winter Storm: Forecast Discussion with Brant Beckman

WEEKEND WINTER STORM

Questions are beginning to arise as to whether or not a major winter storm is expected for the Black Hills Region this weekend into next week.

If you’re going to look at the potential for winter storms more than 3 days out, we have to rely on parameters that do NOT involve specific snow maps – but rather a blend of models called ensembles. These are many model runs that are combined to paint a broad picture of what’s on the horizon…usually this involves lines of pressure (isobars) and temperature trends. We use these because these are (far) more truthful in long range forecasts than specific snow maps.

Ensembles have shown a remarkably consistent strong signature that a large area of low pressure will descend from the Colorado Rockies into the front range, strengthening and deepening as it pushes Northeast.

If the position of the low pressure system holds true in these models, this will allow large amounts of Gulf moisture to be sucked up like a vacuum into the Northern plains and washed over large areas of advancing cooler air. Right now this area looks to be from the Southern Black Hills stretching south through the Nebraska panhandle, Cheyenne and finally the Colorado rockies.

These specific areas have potential to receive large snow amounts – several feet being a reasonable expectation in some cases. Moderately gusty winds and relatively cold temperatures could be expected as well.

Areas just outside of the bullseye can be considered the splash zone… where large snow amounts can’t be ruled out, but will be less likely. Rapid City and areas along/North of I-90 can be considered in this “splash zone”.

However…

Ensembles have been inching this low pressure system North over the last 48 hours – which would bring the Black Hills and Rapid City closer to the bullseye of high impacts. This has not occurred yet – but IS currently trending in this direction.

Remember, even if the Black Hills is not in the bullseye of this event – there could be significant impacts to travel and ranchers in the midst of calving season.

Because of the timing and location of the low pressure system – this could be a multi-day event.

This event looks to start Saturday in the lee of the Rockies and make its way Northeast Saturday night through Sunday and Monday.

SHOULD I MAKE PREPERATIONS?

There is high confidence that a major winter storm will be crossing the front range, within the sights and sounds of the Black Hills.

This is one of those cases where preparations for high snow totals, windy conditions and relatively chilly temperatures…south of the Black Hills particularly…would be well worth it even this far out…the risk of preparing too much for an event of this scale seems small compared to making no preparations at all.

Several detailed forecast discussions will be posted on this event in the coming days – confidence will start to rapidly increase by Friday morning of exact impacts for this weekend.

If you have questions, please feel free to ask – I will do my best to answer them in a timely and detailed manner.