The warm, dry spell that Greater Boston is experiencing continues for the rest of the week and into the weekend, although there will be some differences depending on your location.
Wind direction is always a big factor in our weather but this time of the year it’s particularly notable.
With a chilly ocean to the east, this can create huge temperature differences of as much as 30 degrees from the coast to the inland foothills.
Today and Thursday a westerly wind negates any sea breezes for much of the area. This will allow very warm temperatures to settle in over the next couple of days including highs that will be well into the 80s on Thursday.
The exception is going to be the Cape and the Islands, where it stays notably cooler. The breeze also keeps the fire danger on the high side and red flag warnings are in place through Wednesday evening.
These warnings are issued when the air is particularly dry in combination with dry underbrush. This time of the year, the foliage is still not fully out and last year’s leaves are very dry on the forest floor.
The difference between the amount of moisture in the air and the temperature creates the relative humidity and when that relative humidity is low, as it is this afternoon, it leads to a higher risk of brush fires.
Of course the beautiful weather is allowing most of us to get outside and enjoy the April sunshine.
However, the lack of rain is keeping the pollen quite high and if you’re someone who suffers from tree pollen you may notice it badly this year. Rainfall pulls the pollen grains out of the air and when it’s dry like this they tend to accumulate to extreme levels..
Friday is another warm day, with a twist. An easterly wind will be pushing the warm air farther west during the afternoon This means high temperatures will likely be reached in the late morning along the coastline before falling back. Even inland areas should see a pullback in temperature after 3:00 p.m.
Depending on how strong the push of marine air is, we could see temperatures fall back to the 50s in Boston while still being in the 80s across the Connecticut River valley.
Saturday is a dry and partly sunny day and then things turn somewhat unsettled later Sunday, with our first chance of showers in a while taking us into Patriots Day. There is the risk of rain for the marathon, though the exact forecast for the day to be determined.