Storms are tricky things and forecasts change, but here are the essentials you should keep in mind.
1. Snow is expected to start falling in and around Boston and around 10 a.m. (It arrived a bit early: 8:30 ish, depending on your location. Boston parking ban goes into effect at 10 a.m. Boston and other communities have canceled Friday school.)
2. The storm is traveling north. So Rhode Island and communities to the south will be hit earlier.
3. Cape Cod, the islands and southeastern Mass. are warned to brace for tidal flooding. A blizzard warning is also in effect. (That warning was extended to all of Mass.)
4. A band from the Berkshires to the Cape is expected to see the heaviest snow, perhaps as much as 15 to 16 inches in some areas. (Gov. Charlie Baker at his noon briefing said that new totals may hit 20 inches.)
5.Temperatures are expected to drop throughout the day, hitting a low in some areas of 5 degrees above zero Thursday night.
6. Thunder may result as the storm’s cold collides with the relatively warm weather the region has enjoyed for the last 24 hours.
7. Meteorologists say this storm has the potential to be the worst since 2015. We won’t know, of course, until it is over.
8. The heaviest snow is expected to trail off around 5 p.m. (Boston Mayor Marty Walsh is worried by reports that the storm may last longer, taxing plough crews that have been working since early Thursday morning. Baker said he expects state roads to be operational Friday.)
9. Why close schools and go on an emergency footing before the storm even hits? Because since the Blizzard of 1978 when chaos and loss of life ensued during the commute home, officials have acted proactively.
10. So far this season, we’ve had a bit less than 17 inches of snow. That is nearly 8 inches below the norm.