Statistics
Page built 2026-10-28
Data as of 2026-10-28
Search
Built 2026-10-28 (28 October 2026)

NWMT Demand Forecast Accuracy: Error, Bias and Worst Miss, 28 September to 28 October 2026

The day-ahead demand forecast for NWMT was off by 1.9% on average (mean absolute percentage error) over 719 hours from 28 September to 28 October 2026, and 93% of hours landed within 5% of the reading. Its bias was -0.6%: it ran low on average, an under forecast. The largest miss was 255 MW (23.6%) too high at 14 Oct 2026, 10:00 MDT (UTC-06:00). Dates and times are local (America/Denver).

Key Facts

  • The day-ahead demand forecast for NWMT was off by 1.9% on average (mean absolute percentage error) over 719 hours from 28 September to 28 October 2026, and 93% of hours landed within 5% of the reading. Its bias was -0.6%: it ran low on average, an under forecast. The largest miss was 255 MW (23.6%) too high at 14 Oct 2026, 10:00 MDT (UTC-06:00).
  • Across 53 US grids ranked by average error over their own latest 30 day windows, NWMT came 8 (1 is the smallest error).
  • On average the forecast differed from reported demand by 24 MW, against average demand of 1,241 MW.
  • The forecast was above reported demand in 39% of compared hours.

Forecast Error at a Glance

719 hours from 28 September to 28 October 2026
Average error1.9%
Bias-0.6%
Hours within 5%93%
Worst miss255 MW

Average error is the mean absolute percentage gap between the forecast and reported demand. Bias is the signed mean (-9 MW per hour on average): the forecast ran low on average, an under forecast. The worst miss was 255 MW (23.6%) too high at 14 Oct 2026, 10:00 MDT (UTC-06:00): forecast 1,336 MW, reported 1,081 MW.

Source: U.S. Energy Information Administration (EIA). (US Government work, public domain) Data as of 2026-10-28. Accuracy is computed by World Power Monitor from the operator's hourly forecast and reported demand.

Forecast and Reported Demand, Last 7 Days

Local time, to 28 Oct 2026, 05:00 MDT (UTC-06:00)
NWMT day-ahead demand forecast and reported demand by hour Hourly reported demand and the day-ahead forecast for NWMT over the last 7 days of the window, to 28 Oct 2026, 05:00 MDT (UTC-06:00). Gaps are hours with a missing, zero or implausible report. 0 375 750 1,125 1,500 21 Oct, 06:0022 Oct, 06:0023 Oct, 06:0024 Oct, 06:0025 Oct, 06:0026 Oct, 06:0027 Oct, 06:00
Hourly reported demand and the day-ahead forecast for NWMT over the last 7 days of the window, to 28 Oct 2026, 05:00 MDT (UTC-06:00). Gaps are hours with a missing, zero or implausible report.
Data to 2026-10-28
Show the data table (168 rows)
Local hourReported demandDay-ahead forecast
21 Oct, 06:001,269 MW1,291 MW
21 Oct, 07:001,364 MW1,367 MW
21 Oct, 08:001,360 MW1,366 MW
21 Oct, 09:001,325 MW1,335 MW
21 Oct, 10:001,274 MW1,300 MW
21 Oct, 11:001,257 MW1,269 MW
21 Oct, 12:001,214 MW1,242 MW
21 Oct, 13:001,216 MW1,227 MW
21 Oct, 14:001,206 MW1,225 MW
21 Oct, 15:001,246 MW1,242 MW
21 Oct, 16:001,248 MW1,252 MW
21 Oct, 17:001,282 MW1,287 MW
21 Oct, 18:001,320 MW1,306 MW
21 Oct, 19:001,342 MW1,325 MW
21 Oct, 20:001,315 MW1,301 MW
21 Oct, 21:001,273 MW1,253 MW
21 Oct, 22:001,191 MW1,186 MW
21 Oct, 23:001,140 MW1,130 MW
22 Oct, 00:001,103 MW1,109 MW
22 Oct, 01:001,078 MW1,097 MW
22 Oct, 02:001,078 MW1,078 MW
22 Oct, 03:001,072 MW1,081 MW
22 Oct, 04:001,091 MW1,097 MW
22 Oct, 05:001,160 MW1,153 MW
22 Oct, 06:001,263 MW1,261 MW
22 Oct, 07:001,320 MW1,340 MW
22 Oct, 08:001,330 MW1,343 MW
22 Oct, 09:001,299 MW1,317 MW
22 Oct, 10:001,280 MW1,290 MW
22 Oct, 11:001,244 MW1,264 MW
22 Oct, 12:001,229 MW1,248 MW
22 Oct, 13:001,230 MW1,242 MW
22 Oct, 14:001,231 MW1,248 MW
22 Oct, 15:001,254 MW1,272 MW
22 Oct, 16:001,275 MW1,274 MW
22 Oct, 17:001,285 MW1,307 MW
22 Oct, 18:001,330 MW1,316 MW
22 Oct, 19:001,334 MW1,315 MW
22 Oct, 20:001,315 MW1,292 MW
22 Oct, 21:001,254 MW1,250 MW
22 Oct, 22:001,197 MW1,192 MW
22 Oct, 23:001,129 MW1,137 MW
23 Oct, 00:001,086 MW1,094 MW
23 Oct, 01:001,052 MW1,062 MW
23 Oct, 02:001,042 MW1,061 MW
23 Oct, 03:001,033 MW1,056 MW
23 Oct, 04:001,039 MW1,059 MW
23 Oct, 05:001,104 MW1,093 MW
23 Oct, 06:001,233 MW1,187 MW
23 Oct, 07:001,324 MW1,271 MW
23 Oct, 08:001,362 MW1,298 MW
23 Oct, 09:001,385 MW1,299 MW
23 Oct, 10:001,403 MW1,289 MW
23 Oct, 11:001,380 MW1,272 MW
23 Oct, 12:001,376 MW1,252 MW
23 Oct, 13:001,398 MW1,241 MW
23 Oct, 14:001,404 MW1,228 MW
23 Oct, 15:001,434 MW1,223 MW
23 Oct, 16:001,462 MW1,245 MW
23 Oct, 17:001,479 MW1,268 MW
23 Oct, 18:001,484 MW1,311 MW
23 Oct, 19:001,450 MW1,334 MW
23 Oct, 20:001,389 MW1,310 MW
23 Oct, 21:001,366 MW1,272 MW
23 Oct, 22:001,317 MW1,216 MW
23 Oct, 23:001,276 MW1,159 MW
24 Oct, 00:001,215 MW1,225 MW
24 Oct, 01:001,204 MW1,209 MW
24 Oct, 02:001,196 MW1,197 MW
24 Oct, 03:001,195 MW1,202 MW
24 Oct, 04:001,221 MW1,211 MW
24 Oct, 05:001,222 MW1,228 MW
24 Oct, 06:001,284 MW1,282 MW
24 Oct, 07:001,331 MW1,332 MW
24 Oct, 08:001,392 MW1,362 MW
24 Oct, 09:001,386 MW1,353 MW
24 Oct, 10:001,363 MW1,328 MW
24 Oct, 11:001,323 MW1,296 MW
24 Oct, 12:001,285 MW1,260 MW
24 Oct, 13:001,236 MW1,226 MW
24 Oct, 14:001,222 MW1,210 MW
24 Oct, 15:001,235 MW1,204 MW
24 Oct, 16:001,247 MW1,213 MW
24 Oct, 17:001,269 MW1,259 MW
24 Oct, 18:001,316 MW1,318 MW
24 Oct, 19:001,348 MW1,342 MW
24 Oct, 20:001,343 MW1,322 MW
24 Oct, 21:001,310 MW1,288 MW
24 Oct, 22:001,263 MW1,240 MW
24 Oct, 23:001,230 MW1,188 MW
25 Oct, 00:001,214 MW1,178 MW
25 Oct, 01:001,204 MW1,199 MW
25 Oct, 02:001,209 MW1,186 MW
25 Oct, 03:001,206 MW1,198 MW
25 Oct, 04:001,213 MW1,220 MW
25 Oct, 05:001,225 MW1,244 MW
25 Oct, 06:001,278 MW1,277 MW
25 Oct, 07:001,344 MW1,325 MW
25 Oct, 08:001,374 MW1,358 MW
25 Oct, 09:001,373 MW1,354 MW
25 Oct, 10:001,340 MW1,333 MW
25 Oct, 11:001,337 MW1,308 MW
25 Oct, 12:001,322 MW1,294 MW
25 Oct, 13:001,284 MW1,273 MW
25 Oct, 14:001,293 MW1,260 MW
25 Oct, 15:001,305 MW1,259 MW
25 Oct, 16:001,355 MW1,279 MW
25 Oct, 17:001,398 MW1,333 MW
25 Oct, 18:001,450 MW1,385 MW
25 Oct, 19:001,449 MW1,405 MW
25 Oct, 20:001,416 MW1,383 MW
25 Oct, 21:001,365 MW1,338 MW
25 Oct, 22:001,284 MW1,263 MW
25 Oct, 23:001,232 MW1,201 MW
26 Oct, 00:001,193 MW1,195 MW
26 Oct, 01:001,184 MW1,182 MW
26 Oct, 02:001,171 MW1,177 MW
26 Oct, 03:001,180 MW1,184 MW
26 Oct, 04:001,204 MW1,204 MW
26 Oct, 05:001,261 MW1,263 MW
26 Oct, 06:001,385 MW1,373 MW
26 Oct, 07:001,471 MW1,454 MW
26 Oct, 08:001,474 MW1,455 MW
26 Oct, 09:001,493 MW1,431 MW
26 Oct, 10:001,481 MW1,399 MW
26 Oct, 11:001,453 MW1,369 MW
26 Oct, 12:001,426 MW1,350 MW
26 Oct, 13:001,404 MW1,330 MW
26 Oct, 14:001,374 MW1,317 MW
26 Oct, 15:001,376 MW1,308 MW
26 Oct, 16:001,371 MW1,320 MW
26 Oct, 17:001,412 MW1,354 MW
26 Oct, 18:001,465 MW1,404 MW
26 Oct, 19:001,466 MW1,417 MW
26 Oct, 20:001,442 MW1,389 MW
26 Oct, 21:001,381 MW1,337 MW
26 Oct, 22:001,299 MW1,261 MW
26 Oct, 23:001,241 MW1,198 MW
27 Oct, 00:001,196 MW1,207 MW
27 Oct, 01:001,173 MW1,183 MW
27 Oct, 02:001,172 MW1,178 MW
27 Oct, 03:001,157 MW1,170 MW
27 Oct, 04:001,184 MW1,197 MW
27 Oct, 05:001,259 MW1,238 MW
27 Oct, 06:001,384 MW1,351 MW
27 Oct, 07:001,428 MW1,427 MW
27 Oct, 08:001,426 MW1,432 MW
27 Oct, 09:001,410 MW1,415 MW
27 Oct, 10:001,403 MW1,392 MW
27 Oct, 11:001,362 MW1,367 MW
27 Oct, 12:001,338 MW1,356 MW
27 Oct, 13:001,328 MW1,345 MW
27 Oct, 14:001,342 MW1,335 MW
27 Oct, 15:001,330 MW1,338 MW
27 Oct, 16:001,351 MW1,349 MW
27 Oct, 17:001,370 MW1,378 MW
27 Oct, 18:001,424 MW1,429 MW
27 Oct, 19:001,421 MW1,440 MW
27 Oct, 20:001,393 MW1,410 MW
27 Oct, 21:001,335 MW1,360 MW
27 Oct, 22:001,264 MW1,292 MW
27 Oct, 23:001,222 MW1,233 MW
28 Oct, 00:001,177 MW1,179 MW
28 Oct, 01:001,157 MW1,162 MW
28 Oct, 02:001,160 MW1,156 MW
28 Oct, 03:001,157 MW1,158 MW
28 Oct, 04:001,195 MW1,185 MW
28 Oct, 05:001,266 MW1,248 MW

Assumptions

  • Only hours with both a forecast and a positive demand reading count (719 of 720 hours in the window). Missing and zero values, and readings under 30% or over 3 times the grid's own median for the window, are treated as reporting faults and left out.
  • Error is (forecast minus reported demand) divided by reported demand; average error uses absolute values so high and low misses do not cancel. Bias keeps the sign and does cancel.
  • Reported demand is preliminary and may be revised. A 30 day window is a short sample and one heat wave or holiday can move these figures.
  • US figures are for the EIA balancing authority or region named on this page. US and European grids are ranked separately.
Cite this page
APA 7

World Power Monitor. (2026). NWMT Demand Forecast Accuracy: Error, Bias and Worst Miss. https://worldpowermonitor.com/forecast-accuracy/nwmt/

Plain text

World Power Monitor. NWMT Demand Forecast Accuracy: Error, Bias and Worst Miss. Data as of 2026-10-28. Data from U.S. Energy Information Administration. https://worldpowermonitor.com/forecast-accuracy/nwmt/

BibTeX 
@misc{wpm_forecast_accuracy_nwmt_2026,
  title = {{NWMT Demand Forecast Accuracy: Error, Bias and Worst Miss}},
  author = {{World Power Monitor}},
  year = {2026},
  note = {Data as of 2026-10-28. Data from U.S. Energy Information Administration.},
  url = {https://worldpowermonitor.com/forecast-accuracy/nwmt/}
}

Permalink: https://worldpowermonitor.com/forecast-accuracy/nwmt/

The Copy buttons add today's date as the access date.