Forecast Verifications and Comparisons

A look at how our forecasts have compared to other forecasters and weather models.

2021-2022 Snow Season Verifications

Updated Mar. 7, 2022 at 10am.

Verified forecast: The actual amount of snow that fell was in the expected forecast range. E.g. if the forecast was for 2-5” of snow, and 4” of snow fell, the forecast verified.

Score: This is a rudimentary measure of how accurate the forecast was vs. how large the forecast spread was. Higher scores are awarded for forecasts that verify well with smaller spreads (e.g. 3-6” vs 2-8”), scores are lower if the actual snow amount is significantly out of range.

Overall Verification Rankings

Rank Name Type Avg. W/L
1 Thomas Horner (Highpoint Weather) Forecaster 77% (▼2) 6/0
* Highpoint Weather App Model 76% (▲2) N/A
2 OpenSnow Forecaster 71% 1/0
3 CAIC WRF Model 59% 0/0
4 ECMWF (Euro) Model 58% (▲3) 0/1
5 NAM 12km Model 56% (▲4) 1/1
6 NBM Prob. 50/90 Model 56% (▲4) 0/1
7 NWS NDFD Hybrid 52% (▲2) 0/1
8 GFS Model 50% (▲1) 0/0
9 (▲1) NBM Prob. 25/75 Model 47% (▲3) 0/2
10 (▼1) NBM Deterministic Model 46% (▼3) 0/2

Normalized Score Rankings

Rank Name Type Score W/L
1 OpenSnow Forecaster 0 1/0
2 (▲1) ECMWF (Euro) Model -0.3 (▲2.0) 2/1
3 (▼1) Thomas Horner (Highpoint Weather) Forecaster -1.1 (▲1.1) 2/0
4 CAIC WRF Model -4.4 (▲0.1) 0/0
5 NWS NDFD Hybrid -6.4 (▲0.7) 1/1
6 (▲1) Highpoint Weather App Model -7.3 (▼0.5) 0/0
7 (▼1) NBM Deterministic Model -7.4 (▼0.7) 1/2
8 GFS Model -9.3 (▲0.9) 0/0
9 NBM Prob. 50/90 Model -9.9 (▲0.8) 0/1
10 NAM 12km Model -10.4 (▲1.6) 0/1
11 NBM Prob. 25/75 Model -13.8 (▲2.41) 1/2

Full Comparison

Name Type Avg. Verification Avg. Score Avg. Spread Wet/Dry Bias
CAIC WRF Model 59% 20.0% 5.8 0% (None)
ECMWF (Euro) Model 58% 24.1% 4.5 -13% (Slight wet)
GFS Model 50% 15.1% 4.7 +9% (Non3)
Highpoint Weather App Model 76% 17.2% 10.4 0% (None)
NAM 12km Model 56% 14.0% 5.2 +33% (Very dry)
NBM Deterministic Model 46% 17.0% 3.5 +22% (Very dry)
NBM Prob. 25/75 Model 47% 11.7% 3.7 +43% (Very dry)
NBM Prob. 50/90 Model 56% 14.6% 7.1 +9% (None)
NWS NDFD Hybrid 52% 18.0% 3.5 +19% (Slight dry)
OpenSnow Forecaster 71% 24.4% 5.7 +3% (None)
Thomas Horner (Highpoint Weather) Forecaster 77% 23.3% 6.1 +13% (Slight dry)

Storm Breakdown

Date Verification - Best Verification - Worst Score - Best Score - Worst
Nov. 9-12 Thomas Horner (70%) NWS NDFD (24%) Thomas Horner (21%) NWS NDFD (8%)
Dec. 6-8 Thomas Horner (84%) ECMWF (43%) NBM 25/75 (38%) ECMWF (18%)
Dec. 8-11 Thomas Horner (66%) NBM 25/75 (10%) ECMWF (25%) NBM 25/75 (-20%)
Dec. 14-16 Thomas Horner (87%) NBM Det. (37%) NWS NDFD (30%) NBM Det. (14%)
Dec. 23-25 OpenSnow (71%) NBM 25/75 (6%) OpenSnow (26%) NBM 25/75 (-19%)
Feb. 1-3 Thomas Horner (87%) NWS NDFD (48%) NBM (34%) NBM 50/90 (8%)
Feb. 16-17 Thomas Horner (81%) NAM 12km (30%) Thomas Horner (81%) NAM 12km (4%)
Mar. 4-7 NAM 12km (78%) NBM Det. (27%) ECMWF (32%) NBM Det. (8%)