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Pattern January 2021 - Joyless January

Eastern Greenville county, Spartanburg county, and Cherokee county absolutely hold onto a wedge much longer than anywhere else in the upstate and tend to be the big winners in CAD setups.
 
SWVAwxfan said:
This is not a central SC storm.
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At this point in time, it certainly looks unlikely that central SC will experience anything more than a cold rain. However, there does exist a non-zero chance that should be considered. why? (not in order by importance)

1. NWP Trends have been favorable across the majority of modeling; especially to note the well-respected ECMWF
2. Short-term high resolution have had a tendency lately for stronger, equatorward CAD as we approach T=0 (verified)
3. Planetary + Synoptic Trends towards a miller B H500 composite are evident in modeling. Notably, the increased ridging out west that is shortening the wavelengths allowing the S/W to effectively dig, confluence trending stronger over the Northeast allowing the Parent High Pressure to orientate itself in a more favorable position + the trends southward with the Hudson Bay Block aiding the increased confluence.
4. I think the two most important changes that are responsible for the wintry wx model output is the trend towards higher geopotential heights over the western US, and the trend in the Hudson Bay block shifting southward to a more favorable position in relation to the 50/50 low to center confluence over the Northeast.
5. The ECMWF 250 MB configuration is very similar to high impact CAD events with only a couple more tweaks to match the composite. This should be illustrated in this Gary Lackmann (+ others) Paper: https://journals.ametsoc.org/view/journals/wefo/18/4/1520-0434_2003_018_0641_aoccsa_2_0_co_2.xml?tab_body=fulltext-display
5. Finally, from a climatology standpoint, late Jan into Feb has the highest frequency of classical (dry) CAD events.. so its really not surprising to see these changes towards a more favorable High pressure location.
200wh.conus.png

In the end, nothing may come from this.. composites are only composites... models are only models and change.. no two events are exactly alike.. so we'll just have to see where we fall in the spectrum the next couple of days!
 
Ended up topping out at 52 here today...20 degrees cooler than the forecasted high from GSP in yesterday afternoon’s update and 17 degrees cooler than the mid-morning update this morning. Definitely one of the biggest CAD temperature busts I’ve seen since moving to eastern Union County nearly 11 years ago. The writing really was on the wall yesterday with the 3kNAM and the HRRR both showing the wedge not breaking down.
 
Myfrotho704_ said:
Although I think the GEFS/GFS will cave, I’d wait until they do
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So now we need the Gfs on board but when the Gfs shows us a signifigant winter storm we question if it’s valid .. that’s a funny observation but it holds true it’s just that bad of a model ??‍♂️
 
Nick_boynton_ said:
So now we need the Gfs on board but when the Gfs shows us a signifigant winter storm we question if it’s valid .. that’s a funny observation but it holds true it’s just that bad of a model ??‍♂️
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Yeah, the irony of what the models are showing for the Wednesday and Sunday storms is thick.
 
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