Tag Archives: spring

Cool And Unsettled This Week

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Hello everyone!

As one light snow event races off towards Newfoundland, another waits on our doorstep for tomorrow. Following light snow tomorrow, temps stay cool into Wednesday before warming up ahead of a more significant storm Thursday into Friday. This one should be mainly rain but quite a lot of it is expected. That storm departs Friday night leaving afternoon showers and thunderstorms around for the weekend as we sit under an upper low.

Overview: This Week’s Weather At A Glance

12Z GFS Giving An Overview Of The Week Ahead.
12Z GFS Giving An Overview Of The Week Ahead.

Here’s this week’s weather at a glance for those who just want the short version. I hate to say it, but there are no long term warm ups in the forecast and even the mid/late week warm spell will struggle to top out above 50F. April in Maine is cruel. Details on our two incoming storms are below.

The Setup: Tomorrow’s Snow

12Z RGEM Showing The Setup Tomorrow Morning With Light Snow. Image Credit: Weatherbell
12Z RGEM Showing The Setup Tomorrow Morning With Light Snow. Image Credit: Weatherbell

Low pressure is currently diving SE across the Great Lakes and will be making its way to SNE by tomorrow morning. It will be too far south for significant impacts here in ME but points south could see several inches. Snow will move in around daybreak and move out in the evening. It will be light and accumulations will be similarly unobtrusive. Because this system is much weaker than the one today, no crazy winds are expected.

Tomorrow’s Snow: Weak Upper Support Means Weak Storm

Afternoon Upper Air Analysis Showing Little Support For Tomorrow's Storm. Image Credit: SPC Mesoanalysis
Afternoon Upper Air Analysis Showing Little Support For Tomorrow’s Storm. Image Credit: SPC Mesoanalysis

The reason this storm will remain weak and to the south is that above 15,000 or so feet, the storm doesn’t exist. In the image to the right you can see the upper level footprint of our storm today with very strong winds and a big dip. Tomorrow’s storm? It’s circled in red. If you can see any significant storm there, let me know because I’m having a hard time. The lack of significant upper level support means this one won’t have a chance to intensify or turn NE when it reaches the coast. The net result? Very little snow for ME and NH.

The Setup: Late Week Heavy Rain

12Z GFS Showing The Upper Air Setup For The Late Week Rain. Image Credit: Accuweather
12Z GFS Showing The Upper Air Setup For The Late Week Rain. Image Credit: Accuweather

Our next storm arrives late week with heavy rain likely. Notice the NW/SE orientation of the longwave features. This means that the trough to our west will be feeding tropical air northward into our area on strong S/SE winds. Those S/SE winds also mean that storms will be more likely to move up the coast when they develop as the individual shortwaves rounding the base of the trough. The end result? Heavy rain is likely at some point between Thursday and Friday. Exactly when and exactly how much rain falls has yet to be determined.

Late Week Heavy Rain: The Tropical Connection

12Z GFS Showing The Tropical Connection Available Late Week
12Z GFS Showing The Tropical Connection Available Late Week

When the rain does come, it will bring with it air straight from the tropics as the 12Z GFS PWAT map shows. This helps to establish fairly high confidence we will see heavy rain at some point late this week. The greatest threat for heavy rain will be Thursday night but it could fall any time Thursday or Friday. Guidance is indicating fairly significant rain could fall with amounts likely in the 1-3″ range. This could cause some rapid stream rises so be aware of that potential. Despite that, no widespread flooding issues are expected.

Next Weekend: The Return Of The Cold

12Z GFS Showing An Upper Low Lingering Over The Area Next Weekend. Image Credit: Accuweather
12Z GFS Showing An Upper Low Lingering Over The Area Next Weekend. Image Credit: Accuweather

Looking ahead to next weekend, the upper level low that brought the heavy rain Thursday/Friday will park over our area bringing cool and unsettled conditions. Expect temps to again drop back towards freezing with rain/snow showers possible. No accumulations or organized storm systems are on the horizon but showers driven by daytime heating will likely become a fact of life heading into the second week of April.

I’ll have more updates through the week.

-Jack

From Winter To Spring This Week

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Hello everyone!

The weather over the coming week will be a period of transition from the bitter winds and snows of winter to the warm winds and heavy rains of spring. After you finish complaining about the wintry start to the week, remember that parts of MA and CT are seeing 3-6″ of snow driven by 60-70 mph winds and accompanied by crashing thunder. We’re being cheated out of a fascinating event.

The Setup: This Evening

Evening Water Vapor Satellite Showing The Development Of A Strong And Dynamic Clipper Tonight/Tomorrow Morning. Image Credit: COD
Evening Water Vapor Satellite Showing The Development Of A Strong And Dynamic Clipper Tonight/Tomorrow Morning. Image Credit: COD

An extremely potent disturbance is currently blasting SE across the Eastern Great Lakes. The impressive couplet of strong rising/sinking air indicates this is an extremely strong disturbance. Arctic air is already pouring in behind this storm with winds across the Midwest gusting over 50mph this afternoon. This whole system is moving east quite quickly and will be in New England tomorrow morning. Also going on this evening is the development of an offshore wave embedded in the subtropical moisture feed. This will drag the moisture offshore which is why the arctic disturbance won’t bring us a blockbuster storm.

Light Snow: Tomorrow Morning

12Z RGEM Showing The Setup Tomorrow Morning. We're On The Edge Of This One. Image Credit: Weatherbell
12Z RGEM Showing The Setup Tomorrow Morning. We’re On The Edge Of This One. Image Credit: Weatherbell

The RGEM model is showing what the storm will look like when it’s over our area tomorrow at 8 AM. Most southern areas will see at least a few flakes and York County could see a couple inches. Most just get a dusting if that. The mountains look to remain completely dry. The bulk of this one will be in Southern New England where the higher elevations of eastern CT and MA will see up to 6″ of snow, hurricane force wind gusts, and thundersnow. For those areas, this will be a pretty crazy storm. For everyone, the storm moves quite quickly and is gone by tomorrow afternoon.

High Winds: Tomorrow All Day

12Z GFS Showing Wind Potential Tomorrow.
12Z GFS Showing Wind Potential Tomorrow.

One impact that the mountains and the coast alike will feel will be the winds. Winds under the yellow line are eligible to take a hike to the surface. It is hard to see here but the GFS does have a 50kt contour in the blue circled area Sunday morning for Portland. A good rule of thumb I learned from CBS 13 meteorologist Charlie Lopresti is to take whatever the model puts out for knots in the mixing layer and forecast the same value in mph. That would give us 50mph wind gusts tomorrow morning which seems reasonable based on the strength of the storm. The NWS has issued a Wind Advisory for tomorrow and scattered power outages are certainly possible. Winds subside tomorrow evening.

Bitter Cold: Tomorrow Through Tuesday

18Z NAM Showing Temps Barely Getting To Freezing Monday. Image Credit: Weatherbell
18Z NAM Showing Temps Barely Getting To Freezing Monday. Image Credit: Weatherbell

The core of the Arctic airmass moves overhead Monday and the chill will definitely be felt across the area. Temps look to barely get to freezing (if that) even under the powerful April sun. Despite the bitter cold temps, winds will subside and thus temps may even feel warmer when compared to the bitter winds of Sunday. Temps won’t be going very far up on Tuesday either and it’s not until Thursday that temps get even back to normal which is around 50.

The Setup: Tomorrow Evening

12Z GFS Showing The Upper Level Setup Monday Night Ahead Of Our Next Snow Event. Image Credit: Accuweather
12Z GFS Showing The Upper Level Setup Monday Night Ahead Of Our Next Snow Event. Image Credit: Accuweather

By tomorrow night, our next clipper will be approaching from the west bringing another chance for snow. This is the upper air pattern for the wee hours of Monday morning showing an unfavorable setup for snow. The two disturbances are separate and fairly weak. However, the trough is tilting slightly negative (NW to SE) at the last minute. This is why I think we at least see a little snow out of this storm. The seeds for the return of Spring can be seen across MT. That storm arrives Thursday into Friday.

More Light Snow; Monday

12Z GFS Showing The Likely Impacts For The Monday Storm. Image Credit: Accuweather.
12Z GFS Showing The Likely Impacts For The Monday Storm. Image Credit: Accuweather

The snow from this storm should reach slightly farther north compared to tomorrow’s flakes. Flurries should make it north to around Route 2 or maybe a little north of there. Jackman and points north likely miss out again. The coast and inland points south of Portland likely see steadier snow that adds up to an inch or two. The heavier precip is again to our south over MA and CT where several inches of snow are possible. The main difference compared to Sunday will be the lack of intense winds though there will be some light NE breezes.

The Setup: Late Week

12Z GFS Showing The Setup For The End Of The Week's Return To Spring. Image Credit: Accuweather
12Z GFS Showing The Setup For The End Of The Week’s Return To Spring. Image Credit: Accuweather

By the end of the week, the pattern will have shifted slightly. Weather features in the mid latitudes (us) can be classified into two basic categories: longwave features and shortwave features. The long wave features can often be picked up by models many days out. The development of a longwave trough would lead to a colder/stormier pattern. Shortwaves are responsible for the individual storms that actually drop the rain/snow. These features are not often resolved well on models many days out hence forecast uncertainty in specific impacts. The longwave pattern for the end of the week features a Western ridge and an Eastern trough, both oriented NW to SE (negatively tilted). The longwave trough in the east is situated to our west which will lead to the development of southerly flow aloft.

The Return Of Spring: Heavy Rain Possible Late Week

12Z GEM Showing Heavy Rain Potential Late Week. Image Credit: Weatherbell
12Z GEM Showing Heavy Rain Potential Late Week. Image Credit: Weatherbell

This will bring in a feed of tropical moisture into the area. However, it’s up to the individual shortwaves to put the tropical moisture and thus the heavy rain onto a precise location. Where this is remains up for debate. Anywhere in New England including Maine is in play. Should the storm shift farther east, we may be dealing with a snow event. Should it shift farther west, NY would get the heavy rain while a warm and sticky airmass settles into our area.

I’ll have more details on this storm as we get closer. It looks like the track schedule will allow for evening updates this week. We’ll see how that goes, it’s about as unpredictable as the forecast.

-Jack

A Week Of Wild Weather

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Hello everyone!

This week will serve as exhibit A for the old saying “If you don’t like Maine weather, wait a few minutes”. Tomorrow, lazy spring breezes give way to summer showers and storms. By Sunday, the brisk winds of fall usher in the snows of winter which could drop several inches of snow come Tuesday morning. Not a fan of the snow? By late next week, temps in the 60’s are on the table once again along with rain.

Spring/Summer: Warm And Showery Tomorrow

12Z 4KM NAM Showing Weak Instability Tomorrow. Image Credit: COD
12Z 4KM NAM Showing Weak Instability Tomorrow. Image Credit: COD

Today’s warm breezes continue tomorrow bringing in warmer and, believe it or not, humid air. Dewpoints will rise to near 60 tomorrow which will feel humid this time of year. Temps will range through the 60’s for most. The warm humid air will fuel afternoon showers and storms with the best chance for rumbles in the mountains where the atmosphere is a tad more juiced. No severe weather is expected tomorrow but when thunder roars, go indoors.

Fall: Brisk Winds Deliver Arctic Air Sunday

12Z GFS Showing The Delivery Of Cold Air Sunday. Image Credit: Weatherbell
12Z GFS Showing The Delivery Of Cold Air Sunday. Image Credit: Weatherbell

After getting Spring and Summer out of the way tomorrow, Fall takes over Sunday as a clipper moves through. Rain showers will change to snow squalls as low pressure develops offshore and races east. Winds will be quite gusty as well. On Monday, temps likely will stay near or below freezing as cold air pours in. This sets the stage for the more sizable snow threat on Tuesday.

Winter: Snow Threat Tuesday

12Z GFS Showing A Troublesome Setup Tuesday. Image Credit: Accuweather
12Z GFS Showing A Troublesome Setup Tuesday. Image Credit: Accuweather

Sunday’s cold front stalls offshore Monday as a clipper blasts SE from Alberta. The clipper will move offshore Monday night and a strengthening, negatively tilting upper level trough will help it to intensify. Uncertainty still remains as to the exact track of this storm and thus the exact impacts though some accumulating snow seems likely along the coast. Snow likely moves in Monday night and lasts through Tuesday afternoon. Guidance is fairly far offshore with this storm at the surface but the upper air pattern is giving strong indications that this is likely to drop at least a couple inches along the coast, perhaps a little more.

Spring Returns: Warming Up Late Next Week

12Z GFS Showing The Possible Return To Spring Later Next Week. Image Credit: Accuweather
12Z GFS Showing The Possible Return To Spring Later Next Week. Image Credit: Accuweather

As we head into the latter part of next week, the pattern is likely to modify a bit. The longwave trough in the east is likely to remain but looks to retrograde slightly west and weaken. A flatter pattern out west will allow for the Arctic connection to be cut off and ridging is likely to build over the area. All that jargon translates to a return to normal or above normal temps by the time next weekend rolls around. Current guidance is hinting at heavy rain accompanying this increase in temps but it is far too early to tell specifics. Just know warmer temps are on the way.

A Note On Spring Updates

It’s that time of year again, the sun is out, the birds singing, and the snow flying (sometimes). Spring is here and with it comes Outdoor Track season. Unfortunately, my practice schedule will not allow for evening updates beginning either next week or the week after. I’ll still have morning updates every morning but getting home at 6:30 doesn’t leave a lot of time for forecasting. While I’ve developed a solid system for time management, sometimes high school obligations get in the way.

Thank you all for your patience and continued support, it means a lot.

-Jack

More Messy Weather Tomorrow Into Friday

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Hello everyone!

Early spring is in full swing in Maine and this week will be a good reminder that Spring is a battle between warm and cold. In the beginning, cold wins. Slowly but steadily, the warm air wins out but it will take many messy battles before that happens. For now, the advantage is with the cold. We’ll see that in full swing in the next few days as a powerful Colorado low which is currently bringing every type of weather under the sun from Colorado/Nebraska blizzards to Texas tornadoes. The storm will be significantly weaker by the time it gets to us but will still be potent enough to cause some issues tomorrow into Friday.

The Setup: This Evening

Afternoon Observations Showing Our Next Storm Setting Up To Our West. Image Credit: COD
Afternoon Observations Showing Our Next Storm Setting Up To Our West. Image Credit: COD

A cold front is moving through the area currently (blue line on map) and winds behind it are out of the north which is bringing in cold air. Canadian high pressure is diving SE across Eastern Canada and will continue to supply this cold air through most of the event. Low pressure is moving across the Western plains and will be moving NE towards our area tonight into tomorrow. A warm front extends out ahead of this storm and is linked to the cold front bringing us the cold air this evening. This warm front will try to push north tomorrow and Friday but cold, dry air in place will impede its progress significantly.

Round One: Snow Tonight Into Tomorrow Morning

HRRR Showing Snow Moving In Tomorrow Morning Well Ahead Of The Main Storm. Credit: Weatherbell
HRRR Showing Snow Moving In Tomorrow Morning Well Ahead Of The Main Storm. Credit: Weatherbell

Precip starts late tonight and tomorrow morning in the form of snowfall. Initially, everyone is snow and very light accumulations are likely for everyone by the morning commute. Snow will be light though and major issues are not expected. That tapers off tomorrow morning leaving mid-day tomorrow mainly dry but cool. The main system can be seen at the very end of the loop spreading into western PA/NY.

Round Two: Main Storm: Surface Edition Friday

12Z HRDPS Showing Winds Friday Morning At The Surface. Notice The Warm Winds At The Coast And The Cold High Pressure (No Winds) Holding Strong Inland. Image Credit: Weatherbell
12Z HRDPS Showing Winds Friday Morning At The Surface. Notice The Warm Winds At The Coast And The Cold High Pressure (No Winds) Holding Strong Inland. Image Credit: Weatherbell

The warm front mentioned in the setup section will attempt to move north overnight tomorrow into Friday. It will hit a brick wall at around route 1 which will let temps rise above freezing at the immediate coastline but will keep inland areas below freezing. This pattern should continue through mid afternoon Friday before the low passes overhead and the trailing cold front busts up the inversions holding the low level cold in place. This is the surface pattern that is known far and wide for not changing. Guidance says most of the region goes over to rain by 9 AM. I think it will be 3 or 4 in the afternoon before temps rise above freezing in inland/mountain areas.

Round Two: Main Storm: Upper Air Edition Friday

12Z NAM Showing The Upper Air Setup Friday Morning Over Lewiston.
12Z NAM Showing The Upper Air Setup Friday Morning Over Lewiston.

Aloft, a much different story will play out. There is no Canadian high above 3-4 thousand feet. Therefore, there is no source of cold air. Warm air blasting north will have no trouble pushing the cold air in place out of the way. This will result in a classic mixed precip setup where snow forms in the cold layer really high up before melting in the warm mid levels of the atmosphere. It then refreezes close to the surface resulting in sleet and freezing rain depending on the depth of the cold at the surface. With the cold Canadian high just to our north, there will be a continuous feed of cold dry air being funneled down the east side of the mountains. This is a classic Cold Air Damming setup and CAD always lasts longer than you think even if you think it will last longer than you think. That tongue twister boils down to the fact that cold air moves when it’s good and ready too and it’s not usually to motivated to go anywhere.

Round Two: Main Storm: Impact Map Friday

Expected Impacts From This Storm
Expected Impacts From This Storm

Following the initial snow tomorrow morning, this is what I expect for impacts. Everyone starts out with a little mix but strong SE winds should quickly warm the coast up above freezing resulting in mainly rain there. Despite that, do be prepared for slick conditions everywhere as sleet and freezing rain are a dangerous combo especially with some leftover snow around. Inland, even a few miles, cold air will put up a much mightier fight. Look for snow changing to sleet changing to freezing rain. Sleet and freezing rain look to be the dominant precip types through this event. Snow will quickly change over to a mix as warm air blasts in unimpeded aloft but for most areas away from the coast, the surface high will be enough to keep temps below freezing at the surface for a good long time. In terms of accumulation, in the green area, a trace to a tenth of an inch of ice is expected. In the pink area, a tenth to a quarter inch of ice is expected.

Rounds One And Two Combined Snowfall: Tonight Through Friday

Expected Snowfall Before The Change To Mix/Rain
Expected Snowfall Before The Change To Mix/Rain

Here is what I expect for snowfall before we change to a mix or rain depending on location. While I have the Penobscot Bay and York County regions missing out on any accumulations, I wouldn’t be overly surprised to see coatings there tomorrow morning. This all basically is gone Friday afternoon as sleet and freezing rain turn the ground into an icy crust. The March sun angle is still a factor here despite cloudy conditions and sleet/freezing rain could have a hard time accumulating on pavement. However, please use caution especially Friday as any untreated roads will likely be slick. This snowfall map includes precip tonight and into tomorrow morning.

Round Three: Possible Storm: Early Next Week

12Z GEFS Ensembles Showing The Potential For More Stormy Weather Early Next Week. Image Credit: Weatherbell
12Z GEFS Ensembles Showing The Potential For More Stormy Weather Early Next Week. Image Credit: Weatherbell

Following this storm, we have a nice early Spring weekend to look forward too with cool temps and sunny skies. However, tranquil patterns rarely last long in March in Maine and by early next week, another storm threatens. As you can see here, guidance is converging on the idea we see some sort of precip. How much/what type is still yet to be determined. Snow, mixed precip, and rain are all on the table as well as no storm at all though that is becoming less likely. While it is too early to offer details, I just wanted to put that out there as something to watch in the coming days.

-Jack

 

Winter’s Last Stand Begins Tonight

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Hello everyone!

Our very tricky forecast remains a nail biter as the storm begins to develop off the Carolina coast. A large plume of moisture extends from the Eastern Pacific to the Western Atlantic and two disturbances are dropping in from the NW helping to form the storm. After careful analysis of Water Vapor satellite and observations as well as forecast model guidance, it seems that the more potent disturbance will likely arrive just in the nick of time for the Midcoast but a hair too late for everyone else.

A Comparison Of Observed Reality To Model Forecasts For The Same Time (5 PM This Evening). Image Credit: Accuweather and SPC
A Comparison Of Observed Reality To Model Forecasts For The Same Time (5 PM This Evening). Image Credit: Accuweather and SPC

This is the comparison I’m talking about with regards to the energy blasting through the Great Lakes. Notice the disturbance (marked here by the 534 dm contour line). It is a little farther behind the NAM forecast. These images are valid at the same time (5PM this evening). This is the critical energy that, when it gets here, will tilt the upper level trough negative which will intensify the storm and bring it west. This happens just a little too late for us. Model guidance has backed off on snowfall amounts today, probably as they are sniffing this out. Given that even the most up to date guidance (18Z NAM used here) is too fast with this energy, I’ve opted to go even lower with my snow totals. Without the trough tilting negative, moisture cannot be wrapped west and precip won’t get much past the coast.

HRRR Showing Precip Arriving This Evening. Credit: Weatherbell
HRRR Showing Precip Arriving This Evening. Credit: Weatherbell

In terms of how this all goes down, snow will move in late tonight and be light to moderate through midday tomorrow before tapering off. Really this one only impacts the coast with the mountains and NW foothills seeing but a few flakes. Take a look at the simulated radar above. Those not in the blue (snow) during this loop likely escape with a few flakes, if any at all. The Midcoast could see some heavy snow bands as the storm passes by.

Expected Snowfall Totals
Expected Snowfall Totals

In terms of accumulation, this is what I’m thinking as of now. The Midcoast will see the most as it could get into the heavy bands and will be closer to the center of the storm. A sharp cutoff will occur somewhere near Brunswick but it will be impossible to pinpoint that until the snow is actually falling. West of that cutoff, an inch or so is expected while east of that cutoff several inches are likely. Areas near Camden/Rockland/Belfast are pretty likely to see more than 4″ and up to 6 or 7″ is possible should the banding set up right. Farther north and west, little is expected and the mountains could escape without a flake.

NWS Best/Worse Case Scenarios From This Morning.
NWS Best/Worse Case Scenarios From This Morning.

To give you a sense of how this storm has puzzled even the pros (not just me!), here was what the NWS in Gray thought we could see in the ‘best case scenario’ and ‘worse case scenario’ this morning. This is absolutely not intended to criticize their forecast, this is to show you how uncertain this forecast is. It’s always a good idea to be prepared for the worst case scenario even if it only happens one in every ten times.

All snow wraps up from west to east early tomorrow afternoon with temps rising into the low to mid 30’s and northerly winds strengthening.

This sets up part two of winter’s last stand which will feature snow, sleet, freezing rain, and cold rain to end the week. More details on that tomorrow.

-Jack

Winter’s Comeback: High Impact Winter Storm Possible Sunday Into Monday

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Hello everyone!

Just as the calendar announces the arrival of Spring, our biggest winter storm threat all season is on the horizon. While it is still 3-4 days out, confidence is increasing that a storm will form in the Gulf of Mexico Saturday and move NE until it reaches somewhere near Cape Cod by Monday morning. This track is nearly perfect for heavy snow across the area with the storm being close enough to deliver a lot of moisture and far enough away so any warm air remains well to our SE.

12Z GEM Showing The Setup For A Nor'easter Monday. Image Credit; Weatherbell
12Z GEM Showing The Setup For A Nor’easter Monday. Image Credit; Weatherbell

It is important to note, however, that the storm is still a good 3-4 days away. While track changes are certainly possible, it is becoming more and more likely that we do see a high impact storm beginning Sunday afternoon and lasting through Monday afternoon. Here is the 12Z GEM showing the setup Saturday morning as high pressure builds in and low pressure begins to develop. We will have plenty of cold air to go around as Arctic high pressure builds south. At the onset of the storm, temps will be in the 20’s with dew points in the single digits. That will allow for this to be a mainly snow event. Should the low track a little farther west, some mixing could be an issue so we’ll have to keep an eye out for that in the coming days but as of now, this looks like an all or mostly snow event.

12Z GEFS Ensembles Showing Reasonably High Track Confidence But Slightly Lower Timing Confidence. Image Credit: Weatherbell
12Z GEFS Ensembles Showing Reasonably High Track Confidence But Slightly Lower Timing Confidence. Image Credit: Weatherbell

Confidence in track is reasonably good. Most guidance is indicating low pressure develops in the Gulf of Mexico and moves NE to a point right near Cape Cod. However, intensity and timing are the two variables that remain uncertain. The faster the storm is, the less it can intensify and the less snow it gets even if it takes an optimal track. The slower the storm is, the longer it has to intensify and the more snow we get, assuming the same track. This is why despite moderate-high confidence in track, it remains too early to issue accumulation maps. Uncertainty is still high as to exactly how much snow will fall. However, it is looking more and more likely that this is a 6″+ event. Should a slower/stronger solution play out, upwards of a foot of snow is possible. Should a slower/weaker solution play out, amounts would likely be closer to 6″. Currently, I am leaning much more towards the slower/stronger solution though this far out it is important to keep options open.

I’ll have more on the storm tomorrow evening.

-Jack

A Weak But Messy Storm Tonight Into Tomorrow

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Hello everyone! Precip is moving into the area this evening ahead of the first in a series of weak but messy storm systems that will impact the region in the coming week. This evening, I will focus on the storm moving in tonight and lasting through tomorrow and will save the other storms for updates later this week.

5:00 PM Observations Showing Precip Moving In Associated With Tonight's Storm. Image Credit: COD
5:00 PM Observations Showing Precip Moving In Associated With Tonight’s Storm. Image Credit: COD

Precip is currently moving into the area from the west this evening as shown on radar pictured here. The air at the low levels of the atmosphere is quite dry which is resulting in lots of the precip evaporating before it hits the ground. The main impact of the dry low levels is on temps. As the air saturates, the temperature will drop through a process known as wet-bulbing which occurs when falling precip enters a dry airmass and evaporates resulting in some heat energy being removed from the air. The net result is temps that crash towards the dew point as precip arrives. Temps currently are in the 30’s and 40’s but dew points are in the 20’s and 30’s. Away from the coast especially in the mountains, wet bulbing looks to be enough to allow for a period of mix and snow this evening into tonight. North of route 2, this mix and snow will last through early tomorrow afternoon before precip tapers and temps warm.

HRRR Showing How Precip Evolves This Evening. Credit: Weatherbell
HRRR Showing How Precip Evolves This Evening. Credit: Weatherbell

Snow and sleet accumulations in the north will be generally in the 1-3″ range with some areas at elevation seeing up to 4″. Freezing rain will be a concern as well with up to .1″ of ice potentially causing some slick roads tonight and tomorrow morning. The greatest threat for freezing rain will be north of route 2. Coastal areas will see mainly rain.

We get a brief break tomorrow evening and Wednesday morning before more rain/mix moves in Wednesday and Thursday. A larger storm with significant snow and rain is possible heading into next weekend.

-Jack

Fast Moving Mess Tomorrow

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Hello everyone!

A quick shot of wintry mess is incoming tomorrow as low pressure races to our west. Not much in the way of changes from yesterday though I don’t think the mountains will get as much as initially expected. More 3-6″ amounts are likely as opposed to 6-10″ amounts. The main reason for this is the fact that where the cold air hangs on longest is where the least precip falls. Those that see more precip don’t get as much cold. I’ll show that in more detail below.

18Z GFS Sets Up Our Next Storm. Note The Warmer Westerly Track. Image Credit: Weatherbell
18Z GFS Sets Up Our Next Storm. Note The Warmer Westerly Track. Image Credit: Weatherbell

Low pressure that was originally expected to track right over us now looks to pass to our north tonight into tomorrow morning bringing a quick shot of mess especially for areas in the mountains. The GFS map at left shows the low tracking west, the strong SE winds setting up, as well as an interesting feature in the total precip field (solid colors in picture). It looks like the areas that hold onto the cold stay stuck in between two areas of heavy precip. The areas that see the precip get the cold scoured away. This is why I’ve toned down my snowfall map a bit. I don’t think there’s a very good overlap between the precip and the cold. That being said, where there is even modest overlap, around 6″ of heavy wet snow is likely.

12Z GFS Showing Winds Tomorrow Morning. Image Credit: Accuweather
12Z GFS Showing Winds Tomorrow Morning. Image Credit: Accuweather

Winds will be out of the SE and could get gusty especially for the midcoast tomorrow morning as a narrow tongue of high winds moves overhead. Winds this time around will be no where near as strong as the last two events but gusts to 30mph are likely. No major impacts are likely. These strong winds will help to push nearly everyone above freezing at least for a time tomorrow morning. The mountains see the shortest above freezing window before a cold front sweeps through tomorrow afternoon.

3-1 Graphic 2

Here’s what I’m thinking for precip type and accumulation. The most snow falls in the north closer to the cold air source. Some light icing is likely inland but no major issues are expected. That being said, the AM commute tomorrow could be slick especially north of Fryeburg-Auburn-Augusta.

12Z CMC Showing A Near Miss Late Week. Image Credit: Weatherbell
12Z CMC Showing A Near Miss Late Week. Image Credit: Weatherbell

This winter will try to send a Hail Mary shot our way late week as a storm intensifies offshore. It looks like we see a near miss at this point but any shift NW would bring snow into our area. After this, we’re basically done with winter as temps warm up heading into next week. While the large scale pattern looks toasty, I think we’re on the edge of the true warmth which will be anchored to our west. I wouldn’t be surprised to see a few backdoor cold fronts cool things off in the next few weeks. It’s really hard to get much above 50 in Maine in early/mid March and while I think the coast hangs out around there, I don’t buy the crazy warmth some are showing. However, we definitely do look to warm up solidly above average with temps in the 40’s and 50’s common by the middle of next week.

-Jack

Another Messy Storm Wednesday

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Hello everyone!

A quick update tonight on the next messy storm in the lineup which arrives Wednesday. This one looks to be a fairly simple storm with mountain snow/mix, inland snow/mix/rain and coastal mix/rain. The challenge, as always, will be to pinpoint exactly where those transition spots will set up. The actual storm looks to track right over us and any nudge in the track would result in big changes to the forecast.

12Z GFS Showing The Setup Wednesday Morning. Image Credit: Weatherbell
12Z GFS Showing The Setup Wednesday Morning. Image Credit: Weatherbell

Low pressure that passed north of the region today left a cold front behind and that is currently sitting across the region this evening. Low pressure will develop along the front to our SW tomorrow and will move into our area overnight Wednesday. The low currently looks to track right over the area which means that we get the best of both worlds depending on location. The low passes south of the mountains so they get mainly snow with some respectable amounts possible especially the farther NW you go. The low looks to pass over the foothills so they get the full house of snow, sleet, ice, and rain. The low passes NW of the coast so they get the warm rain treatment. The exact lines between these zones are still blurry and will remain that way until things start playing out Wednesday morning.

12Z GFS Showing The Upper Level Setup Wednesday Evening
12Z GFS Showing The Upper Level Setup Wednesday Evening. Image Credit: Accuweather

The trick to this forecast will be temps aloft. The mid level low will track over the mountains which should let them stay mostly snow. Farther south, even the foothills are on the warm side of the low which means that the stage is set for mixed precip likely in the form of freezing rain. Significant accumulations are not expected but there will likely be widespread slick spots away from the coast Wednesday. Should the track of the mid level low shift to the north, even the mountains mix and less snow falls. If it shifts to the south, the mainly snow area could shift down towards the foothills. Both options are on the table at this point.

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Here is what I’m thinking in terms of accumulation for various precip types. The only area that could get a significant storm looks to be the northern mountains. Everyone else mixes with an assortment of precip types.

A coastal storm misses south late week and then a ridge builds into the east coast which leaves us with building heat heading into next week.

Next winter will be better.

-Jack

Inland Runner To Bring A Mix Of Precip Tonight Through Thursday

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Hello everyone!

Another storm is tracking up the Ohio River Valley this week and it will bring with it a mix of snow, sleet, freezing rain, and rain with the chance for a rumble or two of thunder. This storm is really two storms, one moving offshore tomorrow and another moving to our west Thursday. The first storm has the frozen precip while the second storm has the liquid precip. I’ll break down each and every impact below starting with some snow tonight into early tomorrow morning.

First Storm: Snow

5:00PM Observations Showing The Setup Tonight/Tomorrow Morning. Image Credit: COD
5:00PM Observations Showing The Setup Tonight/Tomorrow Morning. Image Credit: COD

Low pressure is moving NE offshore this evening and will bring us a round of precip tonight into tomorrow morning. Due to a cold dry airmass out ahead of the storm, this precip will start out as snow tonight with a couple inches of accumulation. Warm air will  be blasting in aloft and will change snow over to sleet and freezing rain for the AM commute tomorrow. Before the changeover, a few inches of snow are expected but accumulations should remain fairly light. The snow combined with the icy mix will make for a very slick AM commute so be sure to allow extra time for slow travel tomorrow morning.

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Here is what I expect for snowfall accumulations. The immediate coast could go over to rain fairly quickly so little accumulation is expected there. Most areas see 1-3″ but areas in the far north are likely looking at a good 3-6″ before warm air aloft finally gets up there mid day tomorrow.

First Storm: Ice

18Z NAM Sounding Showing Freezing Rain Potential Tomorrow Morning. Image Credit; Twisterdata.com
18Z NAM Sounding Showing Freezing Rain Potential Tomorrow Morning. Image Credit; Twisterdata.com

Warm air aloft will easily move in tomorrow morning. At the surface however, the cold will put up a solid fight. As a result, freezing rain is expected to be widespread tomorrow. This vertical profile of the atmosphere tomorrow afternoon near Rumford shows what I’m talking about. Snow will form and fall in the upper levels of the atmosphere which are below freezing (upper blue area). They will then fall into an above freezing layer which will feature temps near 5C (41F) and the snow will melt. Just before it falls to the surface, it will encounter more below freezing air. This won’t be cold enough for long enough to refreeze the rain back into sleet but it will be cold enough to allow the rain to freeze on whatever it hits. This is how we get freezing rain. As long as the lowest levels of the atmosphere stay below 32F, ice will continue to pile up. The greatest risk for solid ice accumulation is in the mountains and foothills where cold remains in place the longest. Closer to the coast, the very bottom of the atmosphere will warm faster but a sliver of below freezing air will remain between 500 and 1500 feet in elevation. If you live between those elevations anywhere in Maine, you are at risk for a fairly significant ice event.

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Here are my thoughts on ice accumulation. Keep in mind, areas between 500 and 1500 feet in elevation run the risk of up to .5″ of ice even towards the coast. At lower elevations near the coast, less ice is expected and the immediate shorelines will likely escape the ice for the most part as temps quickly rise to above 32F. Also keep in mind that a half inch (.5″) of ice is enough to cause tree damage so power outages are definitely possible during this time in any areas that do get close to that half inch mark.

Second Storm: Rain

12Z Hi-Res NAM Showing Heavy Rain Thursday Morning. Image Credit: Weatherbell
12Z Hi-Res NAM Showing Heavy Rain Thursday Morning. Image Credit: Weatherbell

Strong southerly winds eventually get rid of any remaining holdouts of cold air. This will occur from SE to NW Wednesday evening into Wednesday night and the job won’t be completely done for the mountain valleys until the wee hours of the morning Thursday just before the heavy precip moves in. When the heavy stuff does move in, temps will be above freezing for all. While the frozen precip risk will be diminished at this point, we do still have two threats: rain and wind. Between 1 and 2″ of rain is expected for everyone across the area and this combined with warm temps could result in some minor drainage flooding. More impactful river flooding is unlikely though we do run the risk of ice jams on the bigger rivers which very well could cause problems. High winds will be possible with a line of heavy showers Thursday morning and a rumble of thunder cannot be ruled out. Heavy rain clears Thursday afternoon with just residual showers through Thursday evening. Gusty westerly winds will bring temps back below freezing Thursday night and an inch or two of upslope snow is likely during this time as well.

Second Storm: Wind

18Z NAM Showing A Strong But Not Ridiculous Low Level Jet Thursday Morning. Image Credit: Weatherbell
18Z NAM Showing A Strong But Not Ridiculous Low Level Jet Thursday Morning. Image Credit: Weatherbell

A band of strong winds aloft will be moving through at the same time the heavy rain will be and thus we run the risk of some of those winds being mixed down to the surface. While these winds could be strong, notice the lack of bright pink/purple we saw last week indicating these winds will be weaker. While I don’t expect any major issues with these winds, I am worried about scattered power outages especially in areas where ice from tomorrow has weakened trees. In terms of how strong I expect the winds to be, coastal areas could see gusts to 50 mph while the rest of the area sees gusts to 40 mph. Winds turn westerly Thursday afternoon and remain gusty but calm down into the 20-30 mph range which should limit any impacts after noon ish Thursday.

To recap, snow moves in tonight followed by ice tomorrow morning. Ice slowly changes to rain from SE to NW Wednesday night with everyone seeing rain by the time heavy precip arrives Thursday morning. Heavy rain will mix down some high winds Thursday morning causing scattered power outages especially in areas where ice on Wednesday has weakened trees. Rain and wind clears out Thursday afternoon as westerly winds bring in cooler and drier air. Upsloping will keep precip up and running in the mountains where an inch or two of snow is likely into Friday morning.

A cold front passes through Saturday night followed by a warm front Monday. Another cold front arrives Tuesday followed by colder temps.

Another update tomorrow morning.

-Jack