BOSTON (CBS) – For the first time in 124 years of history, the Boston Marathon will not be held in April. Until 1968, the marathon took place on April 19, Patriots’ Day. It was then moved to the third Monday in April and has remained there ever since. From a meteorologist’s point of view, that’s about ideal. October in Boston is accompanied by far fewer possible weather complications than April. I don’t have to tell any New Englander that April can be quite temperamental here.
Take a look at the history of the Boston Marathon:
87 degrees April 16, 2012
28 degrees April 19, 1926
And the last two Boston? We had a record 1.57 inches of rain in 2018 and 0.72 ″ of rain in 2019, along with nasty thunder and lightning.
Then there is the sea breeze in April, the water temperatures are freezing in the 40s. So any type of day with a relatively light wind and decent heating of the terrain and you could have a difference of 20 at 30 degrees along the road from Hopkinton to Boston. Runners can literally experience two totally different seasons along the 26 mile course.
In October, sea breezes are virtually non-existent with much warmer ocean temperatures. Earth’s extreme temperatures at either end are also less dramatic. For example, look at the recordings for October 11:
High record: 82
Record low: 32
These are about 5-10 degrees less extreme than typical marathon dates in April.
Essentially, in October there is really very little worry of a severe weather day with one exception, tropical systems. We just passed the peak of our hurricane season in October and there is usually always something to watch in the Atlantic or the Caribbean at this time of year. Of course, the odds of a Boston hitting on any given day are very low.
And that brings us to our first Boston Marathon in October here in 2021.
As we have been following the forecast over the past few weeks, it was pretty clear that the likelihood of an “extreme” weather day was low. Conditions were generally mild, but far from record territory. We haven’t had a frost near Boston yet, heck we haven’t even fallen below 50 in Boston yet (and that’s almost a record for the most recent one). The tropics have also calmed down in recent weeks, currently there is no named system anywhere in the Atlantic basin.
Thinking back to summer and fall here in 2021, if I asked you what you think would be our biggest weather threat on Marathon Monday, I bet you would almost guess one thing: rain. And you would be right! Boston is currently more than a foot of water above average so far this year and we have just come out of the wettest July-August-September period on record, so naturally there would be some rain. in the forecast.
But alas, I come with good news! The latest indications are that any rain we might receive on Sunday and Monday would be very light, patchy and also mobile ahead of the marathon.
Let’s detail the details:
Saturday started with a glimmer of hope. The sun broke through the cloudy scene around Boston first, but we will see the clouds increase during the day. This will keep us relatively cool compared to Thursday and Friday with peaks in the 60s. In my opinion… good jogging weather before the big day!
Sunday is a bit risky. As a high pressure ridge loses its grip on the region, the rain will slide north, bringing difficult conditions offshore. However, these showers will not reach MY Sunday or Monday for that matter! We saw a big improvement on race day as that high pressure is doing just enough to keep the rain out at sea.
So for Monday itself, while Hopkinton might be stuck in the clouds, Boylston Street might have a sun break by the end of the race. Even with a slight chance of showers at the start, most of the day should be dry.
Hourly forecast Monday:
6:00 am: Hopkinton 55, Boston 60, mostly cloudy, NE wind 4-8mph
9am: Hopkinton 60, Boston 65, mostly cloudy, ENE wind 5-10mph
Noon: Temperatures 68-72, sun breaks, wind E 5-10mph
3 p.m .: Low temperatures in the mid-1970s, sun breaks, wind E 5-10mph
6 p.m .: Temperatures 65-69, Pt. Sunny, wind E 4-8mph
Probably a little warmer than most runners would like, but it’s shaping up to be a great day for spectators!
If you are one of the thousands of runners this year, on behalf of the entire WBZ-TV weather team, I wish you good luck and good weather!
As always, I urge you to stay tuned for updated forecasts this weekend on WBZ-TV, CBSBoston.com and CBSN Boston.
Follow Terry on Twitter @TerryWBZ