I'M - National Archives and Records Administration

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0 .4
3. November. All of the Republic of Vietnam is under the influence
of the northeast monsoon. Most cloudiness and precipitation
occur along the east ,cast of the Republic of Vietnam.
The east coast has generally poor overall weathero "Crachin"
spells, with their low stratified overcast, are responsible for
most of the cloud increase. These "'crachins" cause long periods
of overcast skies, drizzle or rains, and poor visibility over
the coastal plain. Afternoon visibilities are good except when
restricted by precipitation. The east coast receives the majority
of the total monthly rainfall, A cooling trend continues
to take place0 Almost half of the total typhoon activity of
the Western Pacific occurs in the South China Sea; therefore,
storm activity is only slightly less in November than October 0
The probability of a typhoon forming and moving into the South
China Sea is once every two years, while the injLdence of tropical
storms is onr per year.
4. Decembero The northeast monsoon has complete influence over
the weathero The east coast of the Republic of Vietnam has typically
poor overall weathero There are many days of light rain
or drizzle, low cloudiness and poor visibility , generally referred
to as ",,rachin" weathero Fog reduces morning visibility in
the northern valleyso The cooling trend continues with some
areas showing a 4 tc 5 degree Fo reduction from November values.
Typhoon activity is greatly diminished in December , but an occassional
tropical storm or typhoon may occur0
5. January0 This is the coldest month of the year in North
Vietnam and along the east coast of the Republic0 In general,
January is a month of decreasing humidity. However, the eastern
coastlands retain thEt~- gener.lly poor overall weather as in
December0
b6 February. "Crachin't spells which began occuring in December,
reach a maximum occurrance in late February0 Long periods of low
overcast skies with drizzle and light rain and poor visibility
prevail over the coastal plains and penetrate the river valleys
far into the interioro Temperatures begin to increase toward the
spring maximum in late February although the increase is slight
due to high frequency of clouds0
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