Current Conditions at Sanborn Field

 

Tuesday: Overcast. Temperatures falling throughout the day. High: 60

 

Tuesday Night: Partly cloudy. Low: 16

 

Wednesday: Cloudy. High: 28 

Wednesday Night: Cloudy. Chance of flurries. Low: 22

 

Thursday: Cloudy. Snow likely. High: 30

 

 

Thanks to IconArchive.com for the icons! 

====================================================================

Discussion:

Don't let the warm temperatures over the past few days fool you, snow is in the forecast for this week! Columbia has already hit it's high temperature for today and temperatures will continue to drop as a cold front makes its way through the area. This chilly weather stick around for the rest of the week with snow moving in Wednesday evening and sticking around until Thursday and potentially even into Thursday night. Snow accumulation should be light, but there could still be some impacts from this storm, such as slick/icy roads. Make sure to keep a look out for weather updates as the storm progresses so that you can stay weather aware. 

-Cade

=================================================================

Forecasters: Cade, Travis

Date Issued: 2/22/2022 10:00AM CST

Technical Discussion: 

 

Deja vu forecasting is the story this week. It will feel a lot like last week as mid-Missouri falls sharply from above average temperatures with another shot at wintry precip later this week. There was consensus between the 06z NAM and GFS in upper-level conditions, but the GFS was quick with moving the initial cold front through the region and more aggressive with temperatures behind it. As such, went primarily with NAM guidance. The NBM was used to get a probabilistic take on total snow accumulations as it is still too early to narrow down deterministic values. 

Zonal flow over much of the CONUS that seen in the upper levels has transitioned to a meridional regime as depicted by RAP analysis of 250-hPa height and winds. The NAM depicts a southwesterly jet streak remaining over Missouri for the entire forecast period. This will help provide forcing for ascent to support possible precipitation given the presence of sufficient moisture. This is reflected by the 500-hPa plots of absolute vorticity with weak, but present, PVA. At this point it is important to note that the upper-level mechanics at play look substantially weaker than the previous two systems Columbia saw this month. 

This event will likely come in the form of two main spouts of precip. Mid-level saturation depicted by 700-hPa RH shows a first wave of moisture moving into the region Wednesday afternoon into Wednesday evening sticking around into Thursday morning. A second, shorter round of saturated air moves in Thursday afternoon and moves off by Thursday evening. The NAM hints at the bulk of the moisture struggling to get this far north with the majority staying south of US 50. The reason for this is evident when looking at 850 hPa. NAM plots of 850-hPa height, wind, and moisture transport vectors (MTVs) show a massive drop off in moisture transport behind the cold front that passed early Tuesday morning. With the approach of the next low-pressure system, low-level winds once again turn out of the SW, but only briefly and weak in nature. A LLJ present in the Lower Mississippi Valley terminates near the Missouri-Arkansas border and the magnitude of the MTVs drops off considerably there with it. With all this in mind, current thinking is a much less significant event than what was seen in the past several weeks with little moisture and pathetic forcing.

Also differing from the past two events is initial p-types. Tuesday fropa put mid-Missouri in a CAA regime and will continue until Wednesday afternoon when the aforementioned wind shift occurs. Cold air will be well in place as NAM soundings favor precipitation starting as snow. PWATs barely touch 0.5 inches with a column that never achieves full saturation. What this event does have going for it is a deep, moist, DGZ that will favor the growth of large flakes, so snow could be heavier for brief periods. The NBM also favors a smaller-scale event with just over 30% probability of seeing 3 inches or more. 

Future forecast shifts should pay close attention to this event and begin to narrow down deterministic snow totals. 

- Travis