BOSTON (CBS) – There is little change to the Marathon Monday forecast.
The current “groundhog day” pattern we have been in (day after day of similar weather) will begin to break down on Friday.
Read: Boston Marathon Guide
Much warmer air will flow in on southwest winds this weekend.
Temperatures on Saturday will soar well into the 60s, nearing 70 degrees.
We climb even higher on Sunday when many towns will flirt with the 80 degree mark. The record of 81 set back in 1945 should be challenged.
Then comes the tricky part.
A cold front will approach from the west, but how quickly it moves through southern New England will be the key to the forecast on Monday.
The most likely scenario would bring the front through during the day on Monday.
This would mean temperatures would still be quite warm and perhaps a wind shift from southwest to west-northwest would be the only sign of the frontal passage.
We are not expecting much if any shower activity.
So here’s our latest forecast for Marathon Monday:
Mainly sunny and warm at the start in Hopkinton, temperatures well over 50, perhaps nearing 60 for the start of the race with a southwest wind.
During the race there will likely be some building clouds and a wind shift from southwest to west-northwest.
Temperatures should top 70 along the race route and at the finish line in Boston as well.
The worst case scenario right now for runners – the cold front slows and we stay in the warm sector during the race on Monday.
Temperatures would easily hit 80 or higher and records would be challenged.
Unfortunately, this is still a scenario we have to consider and prepare for.
You can follow Terry on Twitter at @TerryWBZ.