Complete Results @

Follow the left-panel link from '23nd Annual Snow Storm Contest > Verified Forecasts > ‘17-JAN-22’ to see the complete forecasters’ verification table by station


In the table ...

Yellow cells indicate the best score in category. 

Forecast STP cells:  yellow if within +/- 5% of observed STP.


Blue (Red) cells indicate the 25% (75%) percentile.


SUMSQ:  sum of square errors (measure of forecast accuracy accounting for magnitude and distribution of snowfall)

STP:  storm total precipitation

TAE:  total absolute error
AAE:  average absolute error


Final Standings - all Forecasters



Station by Station Comparison of Top 4 Forecasts and Observed Storm-total Precipitation (STP)


Perfect Forecasts (Batting Average - Forecast Stations with No Error)


Best Station Forecasts (Batting Average - Forecast Stations with Lowest Absolute Error)


Best Station Forecast Busts (Batting Average - Forecast Stations with Highest Absolute Error)


Consensus forecast best @ PVD … IAD

MAX forecast best @ BGM … DCA

MAX forecast less than observed @

MIN forecasts best @ CAR … BDL

MIN forecasts more than observed @




Strong correlation (R = 0.960) between SUMSQ and TAE Z-scores


A dashed Forecast trend line above (below) solid red Observed snowfall line ==> over (under) forecast

R2 value indicates how well the forecast captured the observed snowfall’s variability … i.e., R2 = 0.874 ==> the forecast captured ~87% of the observed snowfall’s variability.



Storm-total snowfalls for SUN  … 16-JAN-22 through TUE … 18-JAN-22 from CDUS41 (CLI) ... CXUS51 (CF6) ... METARs ... and PNS bulletins.

Excellent coverage and reporting.

6- and 7-group precipitation data not carried in METARS.

Snow-to-liquid ratio (SLR) not reported for some stations with measurable snowfall b/c significant liquid and / or freezing precipitation also occurred during the verification period.

Stations observing >= Trace:  24 (89%)
Given stations with measurable snowfall ... stations observing at least:
4" - 5 (19%)
6" - 3 (11%)
8" - 2 (7%)
10" - 1 (4%)

Max snow melt-water (minimum SLR 10:1)
BGM:  1.18"
BTV:  0.57"

Max precipitation (frozen + freezing + liquid)
ORF:  1.97"
EWR:  1.87"
ISP:  1.60"

New daily record(s)
DCA - 2.6" (2.2"; 1965)

BTV - 8.1" (8"; 1909)

Orange cells indicate new daily record.
Trace amounts (0.05") are not included in STP.

Approximate storm-total snowfall courtesy NOHRSC


SFC analysis:  12z ... 17-JAN-22

Image courtesy DOC / NOAA / NWS / NCEP / WPC


Teleconnection time-series data courtesy CPC





Upper air charts courtesy University of WY


SFC analysis:  09z ... 07-JAN-22

Image courtesy DOC / NOAA / NWS / NCEP / WPC




Imagery courtesy George C. Marshall Space Flight Center Earth Science Branch



Radar imagery courtesy College of DuPage NEXLAB