Following yesterday morning’s subfreezing weather ending the growing season in much of the region, much milder air is streaming in this morning as a warm front approaches from the southwest. Mainly along and north of the frontal boundary, rain of varying intensity has been falling. The ribbon of rain will shift northward with the front but no substantial clearing is anticipated until this evening. With a  little luck, however, the sky will brighten and even reveal some splashes of sunshine in places across southern New England by mid to late afternoon with sunset to follow at 6:03pm. The freshening southwesterly wind to 15-30 mph will decrease only slightly tonight resulting in temperatures falling no lower than the upper 50s to lower 60s. The air will become more humid and you will feel that tomorrow when it warms up to the middle 70s. The brisk southwesterly wind will check the highs in the upper 60s to 70 or so at south-facing coastal locations. Expect varying amounts of cloudiness and sunshine with a risk of scattered showers increasing late in the day and during the evening. A cold front is currently chugging across the Midwest with the threat of more spotty severe weather developing in the Ohio Valley and Tennessee Valley later today. This front progresses eastward across New England late tomorrow without any turbulent weather. It will shift offshore tomorrow night with any patchy clouds early Tuesday disappearing followed by a few scattered puffy cumulus clouds during the day. Via a brisk westerly breeze, the air will be much drier again with sunshine sending temperatures up close to 60 for the afternoon high.

Looking ahead, a ridge of high pressure is in the works to govern the regime for the rest of the week. After a disturbance in the upper levels causes variable cloudiness part of Wednesday, the remaining days should be essentially sunny until Saturday when some cloudiness will become more prevalent. Daytime highs will range from the upper 50s along the coast to the middle 60s farther inland away from the daily sea breeze. I am expecting a chunk of energy in the jet stream to evolve into a robust closed-off upper air low pressure system in the Midwest later in the week. Its progress eastward will be inhibited by a locking ridge over the Maritimes. The most likely scenario suggests that a band of rain generated by the upper low will slowly advance toward the region. Presently, it appears this ribbon of rain may be delayed until late Saturday night or Sunday with any initial showers drying up over western New England during Saturday. This ribbon may move sluggishly eastward so with good inflow and upper level support, a solid 24 hour period of drenching rains may materialize Sunday into Monday. It is too premature to be highly confident of the precise timing of this rain but it certainly could be quite wet and windy for the Head Of The Charles Regatta next Sunday. We shall see.

In the meantime, Tropical Storm Rafael is located just under 900 miles south of Bermuda this morning. Its maximum sustained winds of 50mph are projected to spike up to 75-80mph in the next couple days. The steering currents will propel the potential Cat 1 Hurricane close to or just east of Bermuda on Tuesday. After passing the island, Rafael will turn more northeastward and possibly sideswipe lower Newfoundland late Wednesday or early Thursday. There is no threat to New England except for some building surf the second half of this week. For more details, logon to the National Hurricane Center.

With Friday night’s freeze, I am expecting a boost to the fall foliage color in southern New England in the days ahead. With the return of several bright sunny days, we should see more vibrant illuminated color going forward. It was simply stunning over the northern mountains a couple of weeks ago so I am hopeful that it will certainly be better down here in the next couple weeks than it was a year ago. Keep apprised of the changes through our blogs, weathercasts and the  New England Leaf Alert.

Any of us here on the WBZ AccuWeather Team would be more than happy to visit your school with our brand new WBZ AccuWeather Mobile Lab to deliver an educational presentation. For more details on arrangements, check out this link on the CBSBoston web site.

If any new data warrants a change in the above synopsis, I will provide an update this evening. Otherwise, Joe Joyce will deliver his latest WBZ AccuWeather Forecast in the morning and Todd Gutner will follow later in the day. Make it a great week!