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Salt Lake City
National Weather Service Forecast Office

ETA Model Errors on Consecutive Runs

Martin Luther King Weekend (January 14-17, 2000)

Over a 4 day period the ETA model continuously produced widespread significant
precipitation over Utah (approximately 50-75% of the January monthly average) in 48 hour periods. In a series of consecutive model runs, the ETA attempted to break down the ridge over the western U. S. and moisten the low-levels of the atmosphere over Utah. The Overview section provides 4 satellite loops and a 500 mb height analysis loop showing what actually happened. The model predictions vs. observed section shows a variety of forecasts and analyses from the model runs during this period. Finally, the sounding section contrasts forecast/analyzed and observed soundings at SLC

The best way to look at this document is to start with the overview and click on each link and work your way through this title page from top to bottom.


Overview

IR Satellite Images during this period:

Jan 14 | Jan 15 | Jan 16 | Jan 17 |

The Synoptic Scale Pattern:

500mb Height Analysis (Loop)



Model Predictions vs Observed:

Mean sea level pressure | Precipitation | SLC Meteograms | SLC Time Heights |
500mb 24hr Fcsts vs Analysis | 500mb Height Differences (loop) | Precipitable Water |



Soundings:

SLC Observed Soundings | Sounding vs ETA Analysis | 24hr Skew-T FCST vs ETA Analysis | 48hr Skew-T FCST vs ETA Analysis |