Biblical Hebrew Forum

[Harold Holmyard <hholmyard AT ont.com>]

Kelton,
> Check out the NET notes, it has some good stuff.
>
> 48 sn One difficulty here is that it is the west wind that brings rain to Israel (e.g., 1 Kgs 18:41–44). C. H. Toy 
> suggests that the expression is general, referring to a northwest wind – unless it is an error (Proverbs [ICC], 468). 
> J. P. M. van der Ploeg suggests that the saying originated outside the land, perhaps in Egypt ("Prov 25:23, 
> " VT 3 [1953]: 189-92). But this would imply it was current in a place where it made no sense. R. N. Whybray 
> suggests that the solution lies with the verb "brings forth" (lleAxT., t®kholel); he suggests redefining it 
> to mean "repels, holds back" (cf. KJV "driveth away"). Thus, the point would be that the north 
> wind holds back the rain just as an angry look holds back slander (Proverbs [CBC], 149). But the support for this 
> definition is not convincing. Seeing this as a general reference to northerly winds is the preferred solution.
>   

HH: There might be another way to look at the issue, based on 
meteorology. I warn you, though, that I am not very knowledgeable about 
weather. Anyway, here are a couple of short paragraphs about how rain forms:
http://www.weatherwizkids.com/Rain.htm

Water droplets form from warm air. As the warm air rises in the sky it 
cools. Water vapor (invisible water in the air) always exists in our 
air. Warm air holds quite a bit of water. For example, in the summer it 
is usually very humid. When enough of these droplets collect together, 
we see them as clouds. If the clouds are big enough and have enough 
water droplets, the droplets bang together and form even bigger drops. 
When the drops get heavy, they fall because of gravity, and you see and 
feel rain.

What causes rain?

When clouds develop or rain occurs, something is making the air rise. 
Several things can make this happen. Mountains, low-pressure areas, cold 
fronts, and even the jet stream.

HH: Notice that cold fronts are one causative factor for rain. North 
winds can bring a cold front, can't they? Here are some more explanatory 
words:
http://www.princeton.edu/~tprep/tsm/scienceaction/cloud_demonstration.htm

It is often said that warm air can hold more water vapor than cold air 
or that warm air has a greater capacity hold water vapor than cold air. 
Although some meteorologists object to these statements, they are 
conceptually useful if correctly interpreted. At a given temperature 
there is a maximum amount of water vapor that can exist in contact with 
a flat surface of liquid water. When that amount is in the air, the air 
is said to be saturated. There is often less water vapor in the air than 
the saturation amount.

Relative humidity is a way of expressing the amount of water vapor in 
the air as a percentage of the saturation level. 100% relative humidity 
means that the air is saturated. 50% relative humidity means that 1/2 of 
the saturation level of water vapor is in the air. If air at 80% 
relative humidity, for example, is cooled without changing the actual 
amount of water vapor in that air, the relative humidity will increase 
and can reach 100% since the cooler air can "hold" less water vapor. 
Once air is saturated, further cooling can result in condensation if 
there are available surfaces (next section)

HH: My understanding is that 100% relative humidity would imply rain, 
and cold north winds could produce such an effect on relatively 
saturated warm air. Is that correct? Here is another statement 
suggesting that cold weather can produce rain:
http://www.atmos-inc.com/weamod.html

There are two basic mechanisms by which precipitation forms in clouds. 
These are called the "warm rain" and the "cold rain" processes. The term 
"warm rain" was derived after scientists noticed that rain in tropical 
regions often fell from clouds with temperatures never colder than 32°F 
(0°C). Rain is formed in these warm clouds when larger droplets collide 
with and absorb smaller cloud droplets in a process known as coalescence.

The "cold rain" process occurs when temperatures in all or parts of the 
clouds are colder than 32°F. In these colder regions the clouds are 
usually composed of both ice crystals and liquid water droplets. The ice 
crystals which form in this supercooled region grow rapidly, drawing 
moisture from the surrounding cloud droplets, until their weight causes 
them to fall. These falling ice crystals may melt and join with small 
liquid cloud droplets, growing to raindrops in a manner similar to the 
warm rain process. If the ice crystals do not melt, they may grow to 
large snowflakes by agglomeration and reach the ground as snow.

HH: As I said, I am not that knowledgeable, but it seems that cold north 
winds could supply the ice crystals that initiate this cold rain process 
in air already containing droplets of water.

Yours,
Harold Holmyard
.