Tag: Snow

I hadn’t touched on this because it seemed such a non-factor, but with very light snow falling at a time I thought it wouldn’t reach the ground…

Oxford: KOXC 030145Z 28007KT 4SM -SN SCT039 BKN045 OVC050 M06/M12 A3005

Danbury: KDXR 030153Z 26006KT 2 1/2SM -SN BR OVC026 M06/M08 A3008 RMK AO2 SNB00 SLP191 P0000 T10561078

I should acknowledge it.

The latest guidance says less than an inch of snow statewide. It should be gone by sunrise.

No big deal.

This will be brief. I’m not only talking about this entry, but the snow as well! Radar shows snow just to our west, but surface observations have nothing closer than Central New Jersey.

The HRRR model shows the snow arriving within the next hour or two (it’s 3:47 PM) and gone by midnight. Accumulations will be an inch or less for the most part.

The cold is here through the weekend. Snow? Not so much.

As you were.

After my week in sunny and (mostly) warm Southern California it seems I’ve returned simultaneously with winter! There is snow on tap for Friday night into Saturday. It doesn’t look to be a major deal, but snow-is-snow and it’s always a bit of a pain.

There are no textbook storms, but this one is mainly an Alberta Clipper with a little Texas moisture drawn in.

Wednesday evening, the low driving the storm is near the British Columbia-Alberta border. It will sink south a little as it moves east. It will also suck up some moisture now over the Southern Plains. That’s the setup.

This will be all snow. Shoreline, inland, everyone gets snow. It looks to be powdery snow–a high snow:water ratio, 15:1 or more.

It will also be a fast mover. Alberta Clippers get the second half of their name from their speedy entrance and exit. The storm starts late Friday afternoon and ends Saturday morning.

Snow lovers will likely be disappointed. This looks like a few inches tops.

Cold lovers will be happy. The temperature will be in the twenties with the wind chill in the teens.

Sunday will be sunny and even colder

As I write this our winter storm is getting set to exit. There’s a lot of snow on the ground. Some folks will get close to a foot.

OK — I got the accumulation totally wrong. Accumulation is forecast incorrectly more than anything else. It’s a forecast on a forecast on a forecast. Any small, but incorrect, calculation poisons the output.

It has been my mortal enemy since I started forecasting!

It didn’t really matter. The snow came when expected and will leave when expected. Most folks stay home with the numbers I had forecast over the past few days.

By tomorrow most roads should be passable and life will roll on.

When it comes to forecasting snow I am often the outlier. My forecasts tend to be conservative because over time the computer models tend to over forecast. Now, as the snow begins I’m tempted to up the accumulations, especially toward the Rhode Island border.

Is there a real difference between 2-4″ and 3-6″. Practically, no. The pain is just the same. The plows will be out. Cars will slip and slide.

The map from the HRRR (Rapid Refresh) model shows nearly all the state over the 6″ isopleth&#185. That seems high. Well, it seems high today… maybe not by tomorrow morning.

So, let’s go with 3-6″ with the lowest amounts on the shoreline where some rain will mix in. A few inches more are possible in Northeastern Connecticut.

The shoreline from the Connecticut River to the Rhode Island border is an especially difficult part of the forecast. You’ll get more moisture, but a significant percentage will be rain. Get the thought of powdery snow out of your mind.

Statewide from late afternoon into the evening the intensity will ramp up. Don’t be lulled out of the house only to find yourself in snow heavier than you’re comfortable with.

The snow will taper to flurries and snow showers after midnight.

Forecasting snow is the most difficult forecast we do in Connecticut. It’s nearly always a critical forecast for you. The pressure’s on.

&#185 – An isopleth is a line on a map connecting points of equal value. Isopleth is the generic term. There are specifics too, like isobars, isotachs, isohyets, etc.

Forecasting weather is an inexact science. You probably didn’t need me to tell you that. Saturday looks a little different than it did 24 hours ago. No surprise.

I won’t be changing much in duration or precipitation type. However, it does look like more snow than originally anticipated.

Unless it’s a massive snowfall the exact amount of snow isn’t very important. All the slippery is in the first quarter inch! The plow guys will tell you water content/weight is more important than height.

The most likely onset for snow is late morning Saturday. Everyone starts with snow. On the shoreline (especially to the east) there will be some waffling between snow and rain before turning back to all snow. Inland Connecticut stays white start-to-finish.

Yesterday I wrote 1-2″. Today I’ll up that to 2-4″, less on the shoreline, an inch or two more from the casinos northward in Eastern Connecticut.

The snow will start light, but a heavier period is likely as the low pressure system driving the storm rapidly deepens toward evening. The snow should taper to flurries and snow showers by bedtime.

It’s a Nor’easter. We’ll have northeasterly winds through much of the day–nowhere as intense as our last storm.

If you’ve got Saturday travel plans, go early. You can beat the storm north and east or hit mainly rain going south.

Weather is like real estate. The three most important factors are location, location, location. That’s the story for Saturday’s storm. It will be a big deal elsewhere, not here.

That’s not to say we won’t get snow. We will. Not a lot.

Unlike yesterday’s multifaceted system this will be all snow for Connecticut. It starts Saturday morning, gone around sundown. An inch or two statewide is likely. Winds will be light and temperatures at or just below freezing.

Call it touch up snow–just enough to brighten what’s already on the ground.

Unbelievably the European, GFS and NAM all agree!

This forecast took a little more time today. My favorite website for the GFS and NAM models is down. It’s not like these aren’t available everywhere, but you get used to your favorite site’s nuances. At least I do.

The 12z model runs are in, including enough of the European to get a feel for tonight. I’m not going to make many changes, though the turnover to rain inland looks a little quicker than my original read.

Everyone starts with a little snow early this (Wednesday) evening. On the shoreline snow will be replaced by rain within a few hours, with a brief interlude of sleet possible in between. The farther inland you are, the longer the period of snow. Duh!

The European is the coldest of the models, followed by the GFS then NAM. Just a few degrees will make a huge difference, because the rain/snow line in each of these scenarios is close by. I’m also using the Rapid Refresh model which is a very high resolution model that only covers 15 hours and makes discrete calls for most likely precipitation type hour-by-hour.

What you wake up to Thursday morning won’t be the peak accumulation. Rain will ‘settle’ the piles and add weight overnight. Expect a slushy inch or two near the shore with lesser amounts the closer you get to the Rhode Island border. Most of inland Connecticut sees 3-7″, except the higher elevations in the Northwest Hills where a foot could fall.

Because there will be a statewide change to rain before dawn, Thursday’s commute will feature slushy, weighty snow on the roads and sidewalks.

Along with the precipitation there will be strong winds from the northeast. Significant coastal flooding is likely at high tide Wednesday night! Wet snow and strong winds also means scattered power outages.

For Southern New England this is the type of storm we get a few times each winter–a moderate p-i-t-a. We will see worse before spring arrives.

My driveway is wet. My lawn is white. Bunnies have left a trail. Except for the occasional sheets of ice that slide off my roof and crash to the ground it’s a quiet and pretty Christmas Day. I’ll take it!

I didn’t want to come back and convert this into a weather blog, but right now weather’s on my mind. There’s another storm due Wednesday afternoon and it won’t be quite as docile.

This next storm caught my eye while it was still in the Pacific. It drenched the fans at the San Francisco – Seattle football game Sunday night. Today it will bring tornadoes to the Gulf Coast states and a blizzard to Southwestern Oklahoma and nearby Texas.

Most likely we feel its effect beginning Wednesday afternoon. This is another storm where location is important.

There might be some snow or sleet at the start, but for the shoreline this is a nasty rainstorm. Overnight, the moderate to heavy rain will be accompanied by strong gusty winds from the east.

Inland is a different story, because I see a significant period of snow before changing to rain. 4-8″ is a reasonable early guess before the snow is capped.

There will be plenty of rain after the snow, but not enough to wash it away. Instead we’ll be left with heavy, icy, slick snow on roads and sidewalks on a windy Thursday morning.

It’s winter weather. The forecast is never 100% right, but if travel is in your plans Wednesday/Thursday you’re going to need to factor this in.