October 12, 2007

Two large upper air lows have drifted across the central Plains region during the past two weeks, dropping moderate to heavy moisture across eastern Nebraska. Unfortunately, western Nebraska continues to miss out on the beneficial moisture leading to a sharp delineation between the haves and have nots. The upper air pattern during the upcoming two weeks points to yet another significant storm rolling into the central Plains which may lead to further harvest delays across eastern Nebraska and valuable moisture for western Nebraska.

Forecast for October 13-19: Another significant upper air trough will enter the central Plains during the first half of the forecast period. Surface low pressure will develop over northeastern Colorado and slowly move east-northeastward. Scattered showers are expected to develop across the Panhandle during the second half of Oct. 13, with a widespread moisture event impacting the state on Oct. 14. The slow movement of the upper air low will allow rain to linger across western Nebraska during the first half of October 15 and into the evening hours across eastern Nebraska. Preliminary moisture estimates for this storm system are in the 1-3 inch range, with eastern Nebraska having the best chance for excessive moisture. After a brief lull in the weather during the October 16-17, a fast moving system will cross the state on October 18 and bring a chance for showers with accumulations expected to be less than one-half inch. Clear skies will return to the region on October 19. High temperatures will range from the upper 60s to low 70s on October 13, cooling into the upper 50s to low 60s October 14-16 before warming into the upper 60s to mid 70s October 17-19.

Forecast for October 20-26: If weather models are correct, the entire forecast period should remain dry. The system that was projected to move across the state on October 18 is forecast to intensify across the eastern United States and become stationary. In response, upper air ridging will occur across the western U.S. and pull unseasonably cold air into the upper Mississippi Valley region. With this pattern, eastern Nebraska will experience significantly cooler temperatures than western Nebraska. High temperatures on October 20 will be in the upper 60s to low 70s cooling into the upper 40s to upper 50s during October 21-22. It is possible that eastern sections of the state may see freezing temperatures as the cold air remains entrenched just east of Nebraska. Temperatures will slowly improve as the week progresses, with highs in the upper 50s to low 70s on October 23, with mid 60s to mid 70s during the October 24-26 period.

Al Dutcher
Extension State Climatologist