1176 
to blow. (For another account of the cloud sequence 
through a storm, see Rossby [81].) 
After the low has passed north of the observer, if the 
wind continues to shift to north or even northeast, and 
if the high clouds do not clear away, and especially if 
middle clouds continue, a wave is probably forming on 
that portion of the front to the southwest, now quasi- 
stationary and developing into a warm front, and pre- 
cipitation may be expected again soon, particularly if 
the clouds are moving rapidly. 
Though we cannot agree with Schneider-Carius [88] 
that it is naive to think one can forecast from clouds 
alone, it is desirable to emphasize, as did a recent re- 
viewer of Douglas’ Cloud-Reading for Pilots [40], that 
an attitude of caution should be adopted towards fore- 
casts deduced solely from cloud structures, since the 
actual sequences of weather are extremely variable. 
Knowledge of cloud characteristics of air masses and 
fronts on the part of the user of forecasts enhances the 
value of the official forecasts. Brunt [21] wrote: “The 
greatest difficulty which meets the official forecaster is 
probably that of timing. ...The recipient of the fore- 
cast can learn, by careful study of the clouds, to check 
for himself whether the timing of a forecast is correct 
or not, and in many cases can make use of the forecast 
when the timing is wrong... .” 
Desirable Lines of Development 
Though cloud systems are already used in professional 
forecasting, closer attention to clouds should improve 
both local and general forecasting. For better inter- 
pretation of cloud data we need more detailed cloud 
charts, such as those already mentioned [1, 6, 11], and 
many more detailed studies of the sequences of clouds 
in relation to the development and movement of pres- 
sure systems and their fronts. 
For better observations we need more nephoscopes 
and more ceilometers and range finders. Nephoscopes 
should be available at all regularly reporting synoptic 
stations, to facilitate accurate reports of cloud motions. 
This would provide a reliable areal contmuum for 
upper-air conditions between the rather openly spaced 
balloon stations. Ceilometers and range finders, as well 
as nephoscopes, should be installed at all aerological 
stations, to supplement the six-hourly pibal and twelve- 
hourly radiosonde or rawinsonde observations, and to 
provide a continuous picture of aerological changes. 
Wood [102] has suggested that, in the future, auto- 
matic radio weather stations might be equipped with 
television to provide the distant forecaster with a view 
of the types of sky over his synoptic area. For the time 
being, we shall have to be content with photoelectric 
registration of the intensity, degree, and rapidity of 
variation of light from a small spot of sky overhead to 
give a rough representation of cloud type (Falconer 
[43a)). 
By means of photographs taken from a V-2 rocket, 
Bergstrahl [5] has shown the distribution of Cu in dis- 
tinet areas, and Crowson [31] has obtained a composite 
picture of an area of over 500,000 square miles in the 
southwestern United States and northern Mexico. This 
CLOUDS, FOG, AND AIRCRAFT ICING 
comprehensive view made it possible to correlate clouds 
with atmospheric structure on a large scale. The use 
of guided missiles to gather atmospheric data has tre- 
mendous potentialities, he believes. If television is used 
instead of conventional photography, complete cover- 
age can be obtained without the problem of film re- 
covery. 
Although rocket photography technique is well 
adapted to desert areas where clouds are thin, it could 
not do justice to the many layers of damper climates. 
Perhaps the answer here is television both from above 
and below! 
REFERENCES 
1. Auprrt, L., ‘‘Weather over the Tropical Hastern Pacific 
Ocean, 7 and 8 March, 1948.” Bull. Amer. meteor. Soc., 
27: 884-398 (1946). 
2. Ancor, A., Traité élémentaire de météorologie, 2° éd. Paris, 
Gauthier-Villars, 1907. 
3. Bere, H., “Ergebnisse und Kritik von Wolkenmessungen 
europdischer Wetterflugstellen.’’ Beitr. Phys. frei. At- 
mos., 21: 75-91 (1934). (Summary in Meteor. Z., 50: 
452-459 (1933).) 
4. Burcuron, T., “Uber die dreidimensional verkniipfende 
Wetteranalyse.’”’ Geofys. Publ., Vol. 5, No. 6, 111 pp. 
(1928). 
5. Berestraut, T. A., “Photography from the V-2 at Alti- 
tudes Ranging up to 160 km” in Upper Atmosphere Re- 
search. Rep. No. 11, Naval Res. Lab. Rep. R-3171, 1947. 
(See pp. 119-130) 
6. Berxorsky, L., ‘Synoptic Cloud Charts.”’ Bull. Amer. 
meteor. Soc., 28: 105 (1947). 
7. Breutow, F.H., Report on the International Cloud Observa- 
tions May 1, 1896 to July 1, 1897. U.S. Weather Bureau, 
Rep. of Chief, 1898-99, Vol. 2. Washington, D. C., U.S. 
Govt. Printing Office, 1900. 
8. Burrxnes, J., ‘On the Structure of Moving Cyclones.” 
Geofys. Publ., Vol. 1, No. 2,8 pp. (1919). (See pp. 4-6) 
9. —— and Sousnure, H., “‘Life Cycle of Cyclones and the 
Polar Front Theory of Atmospheric Circulation.” Geo- 
fys. Publ., Vol. 3, No. 1, 18 pp. (1922). 
10. BuepKer, W., and Anpre, M. J., Convective Phenomena 
in the Atmosphere. Tech. Rep. to Office Nav. Res., 
Contr. N6-ori-20, Task Order No. 2, Proj. NR 082 003, 
24 pp. Dept. Meteor., Univ. Chicago, 1949. (Also J. 
Meteor., 7: 195-209 (1950).) 
11. Brooks, C. F., “‘A Cloud Cross-Section of a Winter Cy- 
clone.”’ Mon. Wea. Rev. Wash., 48: 26-28 (1920). 
Cloud Observing. Third Quart. Rep., (Harvard-Blue 
Hill) U. S. Weather Bureau Contr. Cwb-8120, 1950. 
(See pp. 24-45) } 
13. —— “Clouds in Aerology (1).’”? Bull. Amer. meteor. Soc., 
22: 335-345 (1941). 
14. —— “Local Forecasting from Clouds” in Grrae, W. R., 
Aeronautical Meteorology, Ist ed. New York, Ronald, 
1925. (See pp. 102-105) 
15. —— ‘The Local, or Heat, Thunderstorm.’’ Mon. Wea. 
Rev. Wash., 50: 281-284 (1922). 
16. —— “Waves, Wind, and Weather’’ in Science from Ship- 
board, pp. 11-52. Washington, D. C., Science Service, — 
1943. (See pp. 31-35) 
17. —— ‘‘A Quartet of Complex Halos and the Weather Which 
Followed Them.”’ Bull. Amer. meteor. Soc., 16: 305-306 
(1935). 
18. —— and Harwoop, E. M., Jr., ‘‘Cloud-Observations in 
12. 
