Good evening everybody, I’m not going to go day by day in this report of expected weather, but just focus on the Grinchmas Storm, including what we know, and what we don’t know.
Briefly (to cover the short period leading to the storm onset on Christmas Eve), It’s going to cold tonight in the upper 20s to low 30s, and clouds will thicken tomorrow with highs in the upper 40s to low 50s with showers by afternoon.
WHAT WE KNOW
We know we’re getting heavy rain of 1.5-4″ with our incoming storm. The moisture plume seen in the first graphic for this report shows DEEP and powerful southerly flow straight out of the Caribbean and Bahamas, right up the eastern seaboard, and into New England due to a strong high to our east, and a strong storm to our northwest, with a developing secondary low along the incoming cold front for Friday.
We know showers will start around mid/late afternoon, light and scattered at first, and then more numerous and heavier as we head toward midnight.
We know the heaviest rain moves through between 4-10am.
We know the rain starts to abate between 10am-1pm from west to east.
We know that mild temps in the 50s and dewpoints in the 50s will cause widespread dense fog tomorrow night, and into early Christmas morning, especially in valley locations where visibilities could be under 1/4 mile, and possibly even under 1/8 mile.
We know that snowpack melt will be rapid, and that entire pack will be gone for many of us by noon on Christmas Day.
We know that this will not only cause street flooding and ponding on road ways, which could lead to hydroplaning, but the rapid melt of 1-3″ of water currently tied up in the snow pack will combine with 1.5-4″ of sky water, resulting flash flooding in spots, and likely Flood Warnings along the CT River, which is forecast to rise into moderate flood stage at Montague and Northampton on Christmas afternoon.
We know that we’re going to see scattered to numerous power outages, and that wind will be gusting 40-60mph from the south and southeast, with the highest winds occurring during the pre-dawn hours into early Christmas morning.
We know after highs on Christmas Day of the low 50s to low 60s on Christmas Day, temps will drop to the upper teens to low 20s late at night, and some lake effect snow showers will be seen in the Berkshires and western hilltowns.
WHAT WE DON’T KNOW
If we’re lucky, the worst of the wind (gusts of 55-70ph) will spare us for much of the WMass region late tomorrow night and especially very early Christmas morning, when the worst of the wind is expected.
Determining how much wind will mix down in a situation like this is the hardest part of prognostication, and this will be no different.
Generally speaking, it appears that north of the Pike in WMass and CMass, temps MAY not rise enough to produce a vertical temperature profile conducive to allowing the bulk of the low level jet streak wind (which will be ripping hard at 75-100mph about half a mile to a mile above our heads) to mix down to the surface.
Provided temps don’t warm up like they’re expected to south of the Pike, and we hang in the upper 40s to mid 50s in the Wind Advisory counties, we will see southerly wind gusts of 35-55mph, which is strong enough to cause some limbs and weak trees to come down and would cause some isolated to perhaps scattered power outages and minor property damage.
However, if our temps in these locations spike into the upper 50s to low 60s as they are expected to in northern CT, southern Worcester County, and in eastern MA, more wind will mix down, creating gusts of 55-70mph, which will cause scattered to widespread outages and moderate to possibly major property damage for some.
I am most concerned for northern CT in the region that I cover, in terms of widespread outage potential.
This means pockets of tree damage, and outages could be extended given the Christmas holiday and the extent of outages.
Very heavy rainfall and convection is also known to take very strong winds aloft and send them right down to the ground.
THE BOTTOM LINE
If you’re celebrating Christmas, you should plan to lose power and have a Plan B, either to use your grill, or prepare food ahead of time.
If I were doing a Christmas thing, I wouldn’t assume I’m going to keep my power the whole time, and everything based on that assumption will go off without a hitch.
Now, what I would hate to see happen is you cancel or majorly change plans and then end up keeping your power, but that’s the risk here.
This is the problem with wind forecasts.
There are winners and losers.
For example, in one wind event earlier this year in the town of Florence, some areas lost power for a very long time, where other parts of town kept power the whole time.
Wind damage and corresponding outages happen in pockets like that, not town or county shaped damage areas.
Anyway, I think I’ve been beating the drum on this for days now, but a big impact storm event is on the way, and I will update you again tomorrow morning.
Have a great night, and please spread the word about this storm. Thanks.
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[HIGH WIND WATCHES HAVE BEEN HOISTED FOR THE BERKSHIRES, TACONICS, NORTHERN LITCHFIELDS AND MUCH OF SOUTHERN VT WEST OF BRATTLEBORO, AS WELL AS NORTHEAST CT AND SOUTHERN WORCESTER COUNTY AND POINTS EAST… FLOOD WATCHES CONTINUE FOR THE LITCHFIELDS, BERKSHIRES, TACONICS AND SOUTHERN VT… WIND ADVISORIES WILL LIKELY FILL IN LATER TODAY FOR THE REST OF WMASS, CT, NORTHERN CMASS AND SOUTHWEST NH… THE GRINCH STORM OF 2020 IS ON THE WAY, SET TO CAUSE TRAVEL PROBLEMS DUE TO HEAVY RAIN, DENSE FOG AND STREET FLOODING, ALONG WITH SCATTERED TO POSSIBLY POCKETS OF WIDESPREAD POWER OUTAGES WHERE WINDS GUST OVER 60MPH AT TIMES, CURRENTLY SLATED FOR THE HIGH WIND WATCH REGIONS MENTIONED ABOVE… 7:05AM WED]
Good morning everybody, oh the amount of fun to be had Christmas Eve and Christmas Day, as if it weren’t already problematic enough.
Sometimes in life, the storms are unrelenting – they just keep coming, one after another. Clearly, we’re moving through one of those times in the world.
But, we can still pick ourselves up, dust ourselves off, start all over, again, as Peter Tosh crooned so famously back in the day.
I feel like I have to hurl myself at adversity at times to get through it, you know, just fling yourself at challenges, dive in, get mucky and messy.
You know, do a big floppy cannonball into the pool of life, get wet, get into it, figure it out, move forward.
What the heck else can we do?
I have tried cowering and hiding, and while that’s an appropriate short-term response at times, it doesn’t make progress, and I’ve reach a point in my life where I must move forward, or try to.
Oh wait, this isn’t my private journal on my yellow pad?
Whoops! Sorry about that!
Now here’s Dave with the weather…
SUMMARY
–Temps are starting in the upper teens in SVT, and 20s to low 30s just about everywhere else with some wind gusts over 20mph in spots
–Wind will die down where it’s active, and we’ll start off with partly to mostly sunny skies, and then seen clouds increase as the day wears on
–Highs today will reach the low to mid 30s in the high terrain, and mid to upper 30s in the valley areas
–As high pressure scoots east of our region tonight, light southerly flow develops, and lows will only reach the mid to upper 20s under mostly cloudy skies
–For Thursday, clouds thicken, and southerly flow strengthens with gusts 20-30mph by afternoon/evening
–Some scattered light showers will be possible before sunset (which occurs around 4:30pm) and highs will reach the low to mid 50s as snow melt begins to occur more rapidly
–Christmas Eve becomes quite rainy with temps hanging near 50º all night long
–Southerly winds will start gusting 30-45mph during the first part of the night
–Dense fog will develop as warmer air moves over the melting snow pack
–Rain will become heavier and produce some street flooding in spots
–By early Christmas morning, strong south to southeasterly winds will likely gust 40-60+mph, the highest over the western hilltowns, Berkshires, Litchfields and southern Greens which will be nearer in elevation to a ripping low level jet streak
–Folks living above 1500-2000 feet should essentially assume they will have power outages, and plan accordingly
–Heavy rain and a squall line moves through during the early morning, and then showers should relax by noon and pass east, with westerly and southwesterly cooler winds moving into the region behind the cold front
–High temps will be achieved in the morning (mid to upper 50s)
–The afternoon should see temps slowly start to fall, with some lake effect snow showers pushing into the Berkshires by the late afternoon or evening
–There won’t be a flash freeze, but temps will bottom out in the teens to low 20s, so any standing water leftover will cause black ice patches early Saturday morning
–Anywhere from 1.5 to as much as 4″ of rain could fall
–This rain may cause areas of flash flooding as it combines with 1-3″ of water tied up in snowpack melting quickly into streams which feed into the larger rivers
The weekend looks colder with fair weather, folks, mostly sunny with highs in the mid to upper 20s Saturday and low to mid 30s Sunday with more rain and snow possible Tuesday and again next Friday (New Year’s Eve, woo hoo!), but let’s stay focused on this major weather holiday headline for now, then deal with what’s after it, when it’s time to.
Have a great day, and remember to consider preparations for the potential weather impacts outlined above (giving yourself extra travel time, food prep in case of outages, securing outdoor loose objects due to wind, etc.).