textproduct: Topeka

KEY MESSAGES

- Two rounds of snowfall are expected with the winter storm set to move through the area tonight through Sunday. The first round comes this evening into Saturday morning, and the second round comes Saturday night into Sunday with a lull in between.

- Forecast snow totals remain largely unchanged with 5-8" along and south of I-70 and 3-5" for counties along the KS/NE border.

- Very cold air moves in today and lasts through Monday morning. The coldest wind chills between -15 and -20 are expected Saturday and Monday mornings.

DISCUSSION

Issued at 456 AM CST Fri Jan 23 2026

Upper air pattern shows a cut-off low off the southern coast of CA and broad cyclonic flow covering much of the rest of the CONUS. Cold front has pushed south through the area and the Arctic sfc high is centered over the Dakotas early this morning. CAA will strengthen through the morning as a result with temperatures not making it out of the single digits north of I-70 and struggling into the teens south. Although gusty winds this morning should gradually subside as we get into this afternoon and especially evening, wind chills will still remain below zero all day and fall to -15 to -20 degrees by Saturday morning. Monday morning sees similar wind chill values, and in the meantime largely stay subzero except for a time Sunday afternoon when they may briefly get above zero.

Regarding the snowfall, overall amounts haven't changed much with this forecast package. The main change was to slow the eastward progression of snowfall this evening due to dry air in the subcloud layer. Forecast soundings vary somewhat on how well saturated this layer becomes in central KS during the afternoon, so have held onto some low PoPs there with confidence increasing between 00-03Z. Further east, soundings look dry in the low levels until between 03- 06Z. It is during the evening and especially overnight hours that isentropic lift becomes the main source of vertical ascent while the northern stream upper trough starts to deepen over the Rockies. There isn't much of a low-level response to this wave, just enough for some weak WAA as 850mb winds turn east to southeasterly. There also isn't a particular area that stands out as having strong frontogenetical forcing with more of a broad area of ascent from isentropic lift. With all this in mind, am still skeptical of QPF being as high as 0.25" or even 0.35" through Saturday morning, especially with the delay in onset time as you go east. Snow ratios between 15-20:1 would help snow to pile up more quickly though, so it would be reasonable to say we could pick up 2-5" with this first round (lower totals north, higher south).

Most CAM guidance has snowfall slowing down or stopping altogether for much of Saturday afternoon. There remains plenty of uncertainty with how the second round plays out Saturday night into Sunday, mainly related to how far south the upper trough (remnants of the aforementioned cut-off low) will track and how much dry air may undercut the snow as low-level winds turn back northerly. An early look at CAM guidance, which currently goes through 06Z Sunday, suggests the bulk of the snow may be south of the area at least through that time frame with areas of light snow into our CWA. This may only give another inch or two on top of the first round. The upper trough axis looks to push most, if not all, of the snow through the area by midday Sunday. By the time all is said and done, counties along the KS/NE border would see 3-5" while areas south have totals forecast in the 5-8" range. Think that higher end of the range is more reasonable for locations that get higher amounts with both rounds, whereas most places would probably be closer to the lower end of that range.

After all the headlines end Monday, we see northwest flow aloft with a weaker wave looking to pass just to our east mid-week. Tuesday is the one day we have temperatures reaching around freezing; otherwise, expect highs in the 20s and lows in the single digits for the next work week.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 531 AM CST Fri Jan 23 2026

Gusty NNE winds will continue through mid to late afternoon before subsiding. Snowfall will then spread west to east late this evening. Have slowed the onset time somewhat due to dry air below the cloud layer, but as snowfall increases in intensity overnight, think IFR conditions are reasonable. LIFR vsby isn't out of the question, but guidance is mixed on that idea so will hold off on going that aggressive in the forecast. In any case, conditions are expected to deteriorate overnight with snowfall likely to continue just beyond this period.

TOP WATCHES/WARNINGS/ADVISORIES

Cold Weather Advisory until noon CST Monday for KSZ008-KSZ009- KSZ010-KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024. Winter Weather Advisory from 6 PM this evening to 6 PM CST Sunday for KSZ008-KSZ009-KSZ010-KSZ011-KSZ012. Winter Storm Warning from 6 PM this evening to 6 PM CST Sunday for KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ026-KSZ034-KSZ035- KSZ036-KSZ037-KSZ038-KSZ039-KSZ040-KSZ054-KSZ055-KSZ056-KSZ058- KSZ059. Cold Weather Advisory from 6 PM this evening to noon CST Monday for KSZ026-KSZ034-KSZ035-KSZ036-KSZ037-KSZ038-KSZ039- KSZ040-KSZ054-KSZ055-KSZ056-KSZ058-KSZ059.