Accession Number:

AD0625094

Title:

TERMINAL WEATHER PREDICTION TECHNIQUES.

Descriptive Note:

Final rept. 1 Oct 64-30 Sep 65,

Corporate Author:

UNITED AIRCRAFT CORP EAST HARTFORD CONN

Personal Author(s):

• Harris,Russell G.
• MacMonegle,James E.

Report Date:

1965-11-01

Pagination or Media Count:

37.0

Abstract:

Regression equations were applied to hemispheric and 24- and 48-hr prognostic charts produced by the Global Weather Centrals 6-level dynamical model to obtain diagnostic and predicted total-cloud-amount patterns. The equations were derived in previous research to express total-cloud amount as a function of parameters defined by concomitant 500-, 700-, and 1000-mb height fields. The total-cloud-amount patterns resulting from the use of these equations in this study were verified by comparing them to total-cloud-amount nephanalyses constructed at the Global Weather Central. The diagnostic skill previously shown by the equations on U. S. station data was maintained over other dense-data mid-latitude areas of the hemisphere. Skill measures were lower when sparse-data i.e., oceanic regions were included in the test areas. This deterioration is ascribed to poorer definition of the upper-level predictor fields, or nephanalysis inaccuracies, or both, in these regions. The mid-latitude diagnostic skill of the equations deteriorated about 30 percent when they were applied to 24-hr prognoses, and from 50 to 70 percent at 48 hours. The equations showed little or no skill in tropical or subtropical latitudes, probably because of the effect of advective predictor parameters based on geostrophic assumptions. Author

Descriptors:

• STATISTICAL ANALYSIS
• MICROMETEOROLOGY
• DYNAMICS

Subject Categories:

• Meteorology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE