January 17 12z NAM frontogenesis and lapse rate valid 1/18 09z
Notes:
The next 4 slides show a closer look at 18 to 27 hour NAM forecasts of 500 to 700 mb frontogenesis on the left, and 700 to 500 mb lapse on the right. The frontogenesis was forecast to move steadily east across New York and Pennsylvania. Mid-level (700-500 mb) lapse rates along and west of the band were forecast to increase from around 5 degrees C per km to over 6 degrees C per km. Click on image for a larger view.
Slide 16