Twenty-second annual meeting. 11 



somewhere about 2 to 3 p.m. Still I would not require a wind to reach the temper- 

 ature of 140° to be honored with our title. But after studying this matter more or 

 less for some time, it has been decided for the purposes of this paper that winds 

 must reach the temperature of 98° to be designated as "hot winds." 



After a correspondence, extending through the past winter, on this matter, be- 

 tween the meteorologist of the U. S. Geological Survey and the Kansas Weather 

 Service, it was decided in the spring to issue a joint circular and a blank form for 

 report of these winds. The following is the circular: 



{The United Stales Geological Survey, in cooperation with the Kansas Weather Service.) 



Washington, D. C, 1 t„„«i- iooh 

 ToPEKA, Kansas. '/June lo, 1889. 



Dear Sir: The widespread prevalence of "hot winds" during recent seasons, attended by the par- 

 tial or complete destruction of the vegetation in their path, has awal^ened the attention of agricultur- 

 ists and meteorologists to the need of a better knowledge of their origin and extent, with a view to 

 the possible amelioration of their destructive effects. Many theories have been advanced as to their 

 "cause and cure," but more accurate and reliable information regarding them seems necessary before 

 giving adherence to any. 



The U. S. Geological Survey, in cooperation with the Kansas Weather Service, purposes to collect 

 the requisite statistics of the " hot winds" of the present season, and to this end requests voluntary re- 

 ports of these phenomena upon blanks which have been prepared for the purpose. A supply of these 

 blanks, with return envelopes, accompanies this letter. The scope of the information desired is indi- 

 cated by the questions on the blanks. 



The preparation of these reports, if made as full and complete as circumstances permit, will be a 

 valuable service to the bureaus undertaking the investigation, and it is hoped will result in practical 

 benefit to the territory affected. 



The general results of the work will be furnished to each observer. 



T. B. Jennings, (Signal Corps,) George E. Curtis, Meteorologist, 



Assistatit Director Kansas Weather Service. U. S. Geological Survey. 



( U. S, Geological Survey, in cooperation with the Kansas Weather Service.) 



REPORT OF HOT WINDS. 



station , county , State, . 



Give distance and direction from nearest post-office, . 



Dates of discontinuance, . 



Time of beginning, . (Give time used — whether R. R. or sun.) 



Time of ending, . 



State whether continuous or discontinuous — especially whether ceasing during night. 



Direction from . (Nearest point north, northeast, east, southeast, south, southwest, west, or 



northwest.) 



Force — Give by scale number the prevailing force, ; the maximum force, ; the time of 



maximum force, . 



Temperature, . (Give highest temperature in the shade.) 



Remarks. (State effects on vegetation, and any other facts pertinent to the subject.) 



A copy of the blank form for "Report of Hot Winds" also accompanies this 

 paper. Criticisms are invited, as it is the pioneer in its line; suggestions will be 

 thankfully received, and valid improvements adopted. 



In answer to this circular a number of " hot winds " have been reported. Dur- 

 ing July these occurred on the 5th, 6th and 7th, 15th, 16th and 17th, and 26th and 

 27th, that of the 15th, 16th and 17th being the most extensive and disastrous. 



A resume will be interesting. On the morning of the 5th there is an area of 

 diminished pressure central near the Black Hills, in Dakota. Its indraught extends 

 to the lake region on the east and to Texas on the south. At Bismarck the wind is 

 northeast and the barometer 29.56; at Rapid City the wind is west and barometer 

 29.52; while over Lake Erie the barometer is 30.20, and in Texas 30.06. By the time 

 of the evening observation, 7 v. m. central time, a change has appeared on the Gov- 

 ernment maps. A hot ivave ( remember the time of day — 7 p.m., that is after 6 p.m., 

 actual time) extends from North Platte, Neb., to Fort Custer, Mon., covering the 

 southwest half of Dakota, with temperatures as follows, viz.: North Platte 94°, Val- 



