Light rain anticipated for Thursday, pollution levels to remain ‘moderate’

Mercedians will wake up to cloudy skies on Thursday morning as forecasters anticipate some light rain throughout the day.

According to Steve Mendenhall, a meteorologist with the National Weather Service in Hanford, there is a 60 percent chance of rain during sunrise and late morning hours. There is a 30 percent chance of rain for afternoon hours.

Since July 1, Merced has received 0.88 of an inch of rainfall, well below the normal of 1.61 inches for this time of year, creating a deficit of 0.73 of an inch, Mendenhall explained.

And while any rain is good news during a four-year drought, recent abnormal weather conditions have contributed to high pollution levels.

Last week, San Joaquin Valley Air Pollution Control District officials announced that higher moisture levels brought on by recent rain were followed by unseasonably high temperatures. This resulted in an inversion layer that trapped fine particulates in the air basin. Pollution levels tripled, resulting in unhealthy air quality throughout Valley counties.

Air district officials said that there was some improvement from last week to this week, but they were unsure of the impact today’s possible rain might have on the Valley’s air quality.

However, Mendenhall does not expect pollution levels to be as extreme as last week.

To see any major improvement in air quality, a storm and strong winds are needed, air officials said.

According to the air district’s Real-Time Air Advisory Network, today’s ozone levels did not exceed Level 1 with no action to protect one’s health needed. But fine particulate matter levels were only “moderate.” With moderate levels, the air district suggests that sensitive individuals consider reducing prolonged outdoor activities. These levels, however, were an improvement from last weekend’s levels, when particulate matter pollution reached Level 5, at about 98 micrograms per cubic meter, which the air district classifies as “very unhealthy.”

The district forecasts that Thursday’s particulate matter levels will remain moderate, at about 70 micrograms per cubic meter.

This story was originally published November 12, 2014 at 5:27 PM with the headline "Light rain anticipated for Thursday, pollution levels to remain ‘moderate’."