By: Stephen McCoy - @stephenmmcc
Expect more sunshine and cool temperatures for the rest of the weekend at Portland International Raceway. Winds from the north to northwest will continue in much of the atmosphere, bringing dry air from Alaska and western Canada to the region. Moisture in the lower levels from the Pacific ocean will cause some partly cloudy conditions in the morning and early afternoon, but are expected to lessen as the day progresses. In recent runs, the models have trended towards cooler temperatures on Saturday, with the afternoon high only reaching the low 70's. As I've stated in the previous forecasts, the air at the surface will be dry enough to not have an effect on the heat index, with values nearly identical to the air temperature.
On Sunday, dry air is expected to move in at the lower levels, in addition to the rest of the atmosphere. The result should be mostly sunny conditions, with a few light clouds. The lack of cloud cover will allow for daytime heating to warm the air at the surface, raising the temperature to the mid 70's. Surface winds are expected to be similar to the rest of the weekend, however some wind gusts around 15 mph are possible into the afternoon.
On Sunday, dry air is expected to move in at the lower levels, in addition to the rest of the atmosphere. The result should be mostly sunny conditions, with a few light clouds. The lack of cloud cover will allow for daytime heating to warm the air at the surface, raising the temperature to the mid 70's. Surface winds are expected to be similar to the rest of the weekend, however some wind gusts around 15 mph are possible into the afternoon.
