WATCH: Weekend Storm Is “Not Wimpy,” but Don’t Panic Yet!
Marty Coniglio, Morning Meteorologist from 9 NEWS, WeatherNation’s affiliate in Denver, CO, explains why model predictions on very large storms in the West have to be taken with a grain of salt at times.
Meteorologists across the country use several different types of models. Some models are better at forecasting winter storms while others can be more tailored to nailing down timing and intensity of tropical systems or non-synoptic weather events. In other words, different models are sometimes better or worse at different times of the year with different types of weather events.
Because of this, Meteorologists have to be careful and very responsible with how much weight they give a particular model run. Knowing the geography of where you’re forecasting is usually the first rule of thumb as some models may or may not respond well to terrain differences and/or current weather patterns that could exacerbate or inhibit a particular storm as it moves in.
The second rule of thumb is monitoring how the models are agreeing approximately 48-36 hours from the time the storm is expected to arrive. Timing is key with weather forecasting. Models can look very impressive and promising too far out, almost too good to be true. This is why it is best to begin an attempt at forecasting a larger storm a few days out and tailoring it as the event gets closer. This requires watching the current conditions along with how the model runs are changing (or a lack thereof) over time and how other models may or may not be agreeing. Often times, storms will show weakening trends as the event gets closer. A handful of times a year, storms can show little change or signs of weakening and remain looking very mature and strong even 24 hours out. In this case, the storm must be monitored closely as it inches closer to the forecast region or as it materializes.
While we are forecasting a big storm this weekend, snow totals with current forecast models are coming in way too high and it seems these models are having a hard time getting a handle on how warm it has been in the central areas of the country in recent weeks. This warming can lead to a lot of the moisture melting as it falls to the ground before it begins accumulating as snow. We think it is definitely likely the Colorado Rockies to the Eastern Plains could see well over a foot of snow (possibly even 2-3 feet in some areas) but some model runs, at this time, are overrating how much snow is likely to begin stacking up as it falls.
Timing of this storm is expected to begin Friday and last several days. Possibly, through Monday. Part of this is forecasted slow-down is due an upper-air blocking pattern that will allow this storm to, in a sense, sit and spin for a few days resulting in a machine of moisture that just lingers well into the weekend and beginning of next week.