The worst day on record was April 15, 1998, with a count of 5,200.

That’s followed by April 19, 2016 (4,620); April 19, 1994 (4,140); April 12, 2017 (4,077); and Friday.

Last year, the peak day was April 19 with 2,154. It was a relatively low peak value, but we had a prolonged stretch of days in the "very high" category in 2018.

A higher count doesn’t necessarily mean that the symptoms are more intense for people who are allergic to a particular tree. Rather, more people are likely to notice symptoms kicking in on the very extreme days, even those who don't usually have issues.

It may get easier to breathe in coming weeks once the trees are spent, but grass pollen always kicks up in late spring and early summer.

Jeremy Hoffman at the Science Museum of Virginia has been analyzing Collie’s 31-year data set, and found that the tree pollen counts on the peak days are getting higher and the date of the peak is trending earlier.

Richmond's tree pollen season begins in February and March, starting with a release of cedar, then maple. April usually brings our highest concentrations of tree pollen, driven by oak and pine.