January Discobs 2026

[pazzo83]

52 minutes ago, WEATHER53 said:

Low if 12 here and I’m noticing humidity is not bone dry overnight and wondering if the snow pack interaction is keeping dew points higher and squashing the radiational?

seems plausible

[wxmeddler]

1 hour ago, WEATHER53 said:

Low if 12 here and I’m noticing humidity is not bone dry overnight and wondering if the snow pack interaction is keeping dew points higher and squashing the radiational?

The thing to realize about dew points in this range is that the difference in water vapor between 10F and 0F is between bupkis, and slightly less than bupkis. Once you get down to negatives you're in "absolute bupkis" territory. 

That is to say that radiational cooling (~200 W/M^2) will absolutely overwhelm whatever tiny vapor pressure is being released by sublimination. Long-Wave radiational cooling will tank the temperatures (and therefore dew points) if given the chance to do so. The only thing that will stop radiational cooling is a blockage of the long wave infrared energy to space (ie. Clouds or Fog).

[rjvanals]

NAM 3k still likes a dusting through the metro this evening 

[MN Transplant]

3 hours ago, pazzo83 said:

is there a good explanation for the big misses from the various model outputs?  Was there a model that was better on our actual realized temps?

The NAM 3km is doing pretty well IMBY, but isn't cold enough in the low-lying areas.  The HRRR is the inverse.  The globals are having all sorts of problems.  The fundamental answer is that the models just have so much trouble handling the very stable winter boundary layer and how much mixing there is.