Weather Study 



881 



U. S. DEPARTMENT OF AGRICULTURE, WEATHER BUREAU 



EXPLANATION OF WEATHER SIGNALS 

 No. j No. 2 No. 3 No. 4 No. 5 



Fair Weather Rain or Snow Local Rain or Snow Temperature Cold Wave 



INTERPRETATION OF DISPLAYS 



No. i, alone, indicates fair weather, stationary temperature. 

 No. 2, alone, indicates rain or snow, stationary temperature. 

 No. 3, alone, indicates local rain or snow, stationary temperature. 

 No. i, with No. 4 above it, indicates fair weather, warmer. 

 No. i, with No. 4 below it, indicates fair weather, colder. 

 No. 2, with No. 4 above it, indicates rain or snow, warmer. 

 No. 2, wjth No. 4 below it, indicates rain or snow, colder. 

 No. 3, with No. 4 above it, indicates local rain or snow, warmer. 

 No. 3, with No. 4 below it, indicates local rain or snow colder. 



WILLIS L. MOORE. 



Chief U. S. Weather Bureau. 



EXPLANATION OP WHISTLE SIGNALS 



A warning blast of fifteen to twenty seconds duration is sounded to attract atten- 

 tion. After this warning the longer blasts (of four to six seconds duration) refer to 

 weather, and shorter blasts (of one to three seconds duration) refer to temperature; 

 those for weather are sounded first. 



Blasts Indicate. 



One long Fair weather. 



Two long Rain or snow. 



Three long Local rain or snow. 



Blasts. Indicate. 



One short Lower temperature. 



Two short Higher temperature. 



Three short Cold wave. 



By repeating each combination a few times, with intervals of ten seconds, liability 

 to error in reading the signals may be avoided. 



STORM AND HURRICANE WARNINGS 



Storm warnings. 



Hurricane 

 warning. 



NE. winds 



SE. winds. 



NW. winds. 



SW. winds. 



EXPLANATION OF STORM AND HURRICANE SIGNALS 



Storm warning A red flag with a black center indicates that a storm of marked violence is expected. 



The pennants displayed with the flags indicate the direction of the wind; red, easterly (from north- 

 east to south) ; white (westerly from southwest to north). The pennant above the flag indicates that 

 the wind is expected to blow from the northerly quadrants; below from the southerly quadrants. 



By night a red light indicates easterly winds and a white light below a red light westerly winds. 



Hurricane warning Two red flags with black centers displayed one above the other indicates the 

 expected approach of a tropical hurricane or one of those extremely severe and dangerous storms which 

 occasionally move across the Lakes and northern Atlantic coast. 



No night hurricane warnings are displayed. 



