SPRINGFIELD, Mass. (WWLP) – Many people think being near the ocean is the reason the northeast is humid. But that’s not the only reason — think of the west coast. The west coast is much less humid than the east coast, and it’s because of the temperature of the Pacific versus the Atlantic. Both the Atlantic and Pacific oceans have clockwise flow.
On the west coast, this leads to cold water flowing from the north, but on the east coast, this leads to warm water flowing in from the south near the equator.
On the west coast, winds blow from the west, which brings in that air that is cooled from the water below.
On the east coast, high-level winds are primarily south, which brings in the air that is warmed from the ocean water below. Scientifically speaking, warm air holds more moisture than cool air. So the cool air on the west coast leads to dropping humidity, while the warmer air blowing in to the east coast from the Gulf is filled with moisture.
Right now, the jet stream is positioned in such a way that it’s dragging in cooler air from the north, which holds less moisture. But later this week, we’ll go back to our usual pattern of upper-level winds blowing in from the south.
Humidity makes such a difference in how a day feels. That’s because air that is humid makes it harder for the sweat on your skin to evaporate, which is what cools you off.
A day with low humidity makes it easier for the moisture on your skin to evaporate, so your body can cool properly.
Dew point is the best measure of humidity, and Monday they are in the 30s, which is considered extremely dry.