Dramatic temperature drop followed by "pollen storm" in Boston area

By Terry Eliasen, Meteorologist, WBZ-TV Executive Weather Producer 

BOSTON - The final day of May!  That sure went by fast. 

The undeniable story of the day has been the backdoor cold front and the pollen storm it has created! We started this morning very warm, many locations sneaking into the low 80s before 9 a.m.! Typically, when you think of a cold front, you envision something moving from west to east across the state. This time, the push of cooler air is coming from the east, down the coastline from Maine.

All morning long, as the front arrived, the winds shifted from westerly to easterly, dropping temperatures about 20 degrees in a matter of minutes. In Boston, temperatures dropped from 82 degrees at 8:40 a.m. to 63 degrees by 8:50 a.m.!

What made this even more interesting was the wall of pollen that came along with the cooler air! If you were out and about this morning, you likely came across a green-ish haze. Perhaps you thought there was a wildfire nearby? Nope…just pollen. Lots and lots of tree pollen. Gross.

It was sort of a "perfect storm" this morning. First, you had a couple of warm days with light winds in the peak of the pollen season (last few days). So, much like dust in the desert out west, the pollen was just lying on the surface of everything. . . trees, cars, etc.  Then, as the backdoor front arrived, the gust of wind lifted the green goop into the air, almost resembling a haboob (dust storm seen in the Desert Southwest).

The wall of pollen was so dramatic, it could even be seen on doppler radar as a thin line, right along the cold front!

Ok so where do we go from here??

WEDNESDAY: Mainly cloudy with some periods of rain, much appreciated given the pollen right now. .  . Cooler, highs in the 60s, stiff easterly wind.

THURSDAY: Likely starts cloudy with sunshine developing here and there, highs near 70.

FRIDAY: Clouds return along with some showers. Friday is a big HS graduation day, so timing the rain will be very important. .  . Will be breaking it down in the days to come. High temperatures 65-70.

THE WEEKEND: Looks great!  Mainly sunny both days, highs in the 70s!