An upper-level low will develop and slide over the great lakes Saturday night and will move over New York and New England Sunday and Sunday night. It will be weakening as it moves over New England. This will spread snow showers and light snow to the area dumping up to 3 inches of snow to wake up too Monday morning mainly in western and central southern New England. At the same an upper-level low will slide down from southeast Canada and will push down into Maine creating possible ocean effect snow showers for parts of the coast mainly the outer cape.
Now you probably have heard chatter about a possible good size winter storm in the long range forecasts. The opportunity is certainly there. We will have a better handle of this system possible impacts to the Northeast Monday and Tuesday when all the pieces are over North America.
Current thoughts. Currently I am throwing out the GFS weather model even its ensembles been trash since its update, I just do not trust it. The forecast for this system of course is complicated. When is it not. The placement and strength of high pressure in canada, to the amount of cold air available to how strong is the surface low over the plains under the upper level low in the plains and timing of the transfer of energy from the parent low to the secondary low off the mid-Atlantic coast will all impact what this system brings to the I95 corridor and others in the Northeast.
Above is just one possible outcome for this storm system by EURO weather model Not a forecast but close to what I think may happen based on ensembles. Upper level low goes from central plains to northern plains and then pushed southeast into the Ohio River Valley and Mid-Atlantic. You see some 500v energy pushing through southeast Thursday/Friday, that is the kick starter of the coastal surface low, eventually the upper level low catches up to the surface low off the Mid-Atlantic/Northeast Coast as that energy swings out to sea.
A strong pacific coastal storm and associated upper-level low will spread rain and snow from southern British Colombia to central California. Rain showers and snow can make it all the way down to southern California and desert southwest. A surface low will redevelop under the upper level low over the central plains and looks to kind of stall over the northern plains Wednesday/Thursday as an area of high pressure over southern Canada blocks it from moving north. As the upper-level low moves east/southeast energy will start to converge in the southeast spreading rain showers and thunderstorms with a possible coastal storm developing off the Mid-Atlantic coast Thursday and Friday on the southeast edge of the upper-level low which will still be centered over the Ohio River Valley.
Eventually the upper-level low will reach the mid-atlantic coast Friday night and the original coastal surface low somewhere south of New England could realigned closer to the center of the upper level low, it then based on current guidance we could see it strengthen and we may have a (all southern new England snow lovers 5 favorite words) nor-easter going through the Benchmark. If current thoughts are on the right track, this would be a long duration event. More details to come.
Long range, an active pattern continues, and we could have one of the best winter patterns in December we have not seen in a long time in December. Dare I say it, the odds of a white and cold Christmas is elevated for many.
In this crazy unpredictable world we live in currently one thing that has become a norm as of late is active Atlantic hurricane seasons in terms of number of named systems.
Long range climate drivers are hinting at another active hurricane season.
A look at the sea surface temperature map, we can see that the SSTS are similar to last year. With a clear La-Nina, (1) with a negative pacific decadal oscillation (2. (cool water off west coast)) with a warm west and north Atlantic and a near average to below average MDR (3) . A difference is the Indian Dipole pattern which is cool off the coast of east Africa ( 6) We have warm ocean temperatures across most of the equatorial Atlantic including the “Atlantic Nino region (area 4) but this may change.
ENSO (Area 1) is one of the most important aspects of seasonal forecasting.
Strong easterlies over the equatorial Pacific is maintaining the cold surface temperatures over the ENSO region keeping the warm SSTs over the western equatorial Pacific (Coral Triangle). Last month we were seeing warm anomalies propagations subsurface, and models were seeing this showing a weakening negative ENSO, instead though the stronger easterlies are creating strong upwelling in the east and is preventing warm water from the west being able to establish itself. I am not expecting it to stay this strong, but I am not expecting those warmer ENSO solutions models were showing in the January and February updates. The trend for these have been going cooler. We do have to monitor the current warm SSTS in the Nino 1+2 regions off of South America which are currently above normal, but this is shallow warmth and could quickly return to negative anomalies. the 1+2 Nino region is highly variable.
The Southern Oscillation Index of the Pacific is positive and continued to go positive this is helping to keep La-Nina in place though in past few weeks have come down a bit. When this is positive it favors La-Nina when its negative El-Nino.
Currently La-Nina solidly in place though a slight rise from early to mid March in line with the SOI.Models depicting ENSO 3.4 region to stay negative or cool neutral.Forecast 3.4 region enso forecast by models showing Negative to neutral with the ECMWF being neutral. This becomes important when looking at the ECMWF
The PDO is negative, which enhances La-Nina conditions and looks to stay negative to neutral through the summer.
The Indian Dipole is negative which has been linked to hurricane activity.
In the Atlantic, the Atlantic Nino region is above normal for now but there are signs that this area could go negative as we get into summer. This along with warm ocean temperatures over the higher latitudes in the Atlantic could lead to higher latitude storm systems this season. This also helps lead to decrease Saharan dust out breaks by increasing moisture over North Africa. We will have to also continue to monitor the AMO as we go through the spring. The GOM, Caribbean, and Western Atlantic will be more than warm enough to support activity come the start of Hurricane season but it might take until August for the eastern MDR to become warm enough.
Climate models are advertising an above normal Atlantic season.
Many showing above average precipitation over the MDR, Caribbean ,Gulf of Mexico and portions of the east coast.
They are showing 500mb patterns favorable for threatening tropical activity over the Northern and eastern Caribbean, Bahamas, portions of the Gulf of Mexico and east coast.
Models are depicting below average wind shear over the western MDR and Caribbean. Mix signals of shear over the Gulf of Mexico and eastern MDR. This is in relation to the possible warm pool in Nino 1+2 regions depicted on some models to stay while others remove it. Wind shear could possibly help limit strengthening systems in the western Gulf of Mexico and Caribbean.
Several models are depicting the 200 vorticity potential to be favorable in the MJO 1-4 regions.
Above average precipitation anomalies over the MDR, Caribbean and Gulf of Mexico based off the CANSIPS model. The Cansips is also showing below average Shear over the Western MDR, Caribbean, and Gulf of Mexico June to October
Wind shear
Climate models are showing below average wind shear over the Caribbean through most of the season, with the wind shear increasing over the lower latitudes and eastern MDR by peak season. This could decrease the threat of those big long traveling hurricanes but could also increase the threat across the Caribbean as it could allow the weaker systems to travel further west again increasing the threat to the eastern and northern Caribbean Islands and Bahamas. Models are mixed in terms of the shear over the Gulf of Mexico.
Models are also shaping up a favorable 200V pattern with rising air over the Indian ocean and Africa. Above is the CFS which is one of the further east with the rising air (Green) with neutral over Africa and sinking air over the eastern Pacific. The ECMWF is further west over the Indian ocean and Africa. Both in the MJO 1 to 3 regions which are favorable positions for Atlantic hurricane season.NMME climate model showing above average precipitation anomalies from west Africa to the Caribbean as well. The NMME is a blend of several North American models.
The ECMWF has issued a very very aggressive first forecast for hurricane season . The ECMWF issues a forecast for accumulated cyclone energy (ACE), Hurricane and tropical storm frequency starting March of each year. The first forecast goes from April through September so it does not include all of hurricane season. An update will occur late this week.
Of particular note, since 2015 the number of hurricanes and tropical storms have been on the higher end of the ranges or well above the predictions.
This year’s March ACE forecast at 120% of the average is way higher than the previous two season’s. March Ace forecasts both of which were record breaking seasons in terms of number of storms but not in terms of ACE.
ECMWF is showing above normal tropical storms and hurricanes for the Atlantic basin and with the ECMWF recent conservative bias I would not be surprised if the April update is higher. Also of note, the ECMWF is one of the warmer 3.4 ENSO region predictions.
Another aspect of seasonal forecasting that many rely on are analog years.
This year based on SSTS and patterns these are the analog years I am going with. A note due to climate drivers and climate change I do not generally like to go past the 1990s
Years 1989, 2000, 2011, 2012, 2018, 2021
Numbers of each based on analog years
Analog Range Analog Average
Tropical depressions 15-21 18.3
Tropical storms 11-21 16.67
Hurricanes 7-10 7.8
Major hurricanes 2-4 2.8
Forecast for the 2022 Atlantic Hurricane season
Another active season is looking likely based on SSTS, other climate factors and analog years.
16-22 named storms with 6 to 10 being hurricanes with 3 major hurricanes with an ACE score or Accumulated Cyclone energy score of 130 to 150. An average season has 14 named storms, 7 hurricanes, 3 major hurricanes and ace score of 72 to 111.
Areas of above average Risk for tropical activity directly impacting them will be the Lesser and Greater Antilles, Bahamas, Florida and the East Coast. The western Gulf coast has an average risk for activity directly impacting them.
A major storm track will likely involved a storm track starting in the western MDR to the east of the Lesser Antilles moving through these Islands or to the north of them into the Bahamas. There could be long track storms that accumulate the ACE earlier than usual this season due to increased moisture over North Africa and below average shear.
For this season like last year the weekly updates will start in May with the set up ;
Active storm information: No active tropical activity
Friday a shortwave and surface cold front will move through the area creating the chance of some snow showers Friday. Then a major coastal storm looks to develop off the mid-Atlantic coast. Though there has been rather good consistency in the ensembles discrepancy between the operational deterministic models such as the classic EURO/EPS VS GFS/GEFS model fight. The models have small but significant disagreements with how the upper air pattern of the northern and southern stream energy interacts. The more these interact and the stronger it is the further west and more amplified the upper level low/ or strong trough and therefore the strength of the surface low. The placement of this digging trough Friday night will end up determining the track of the surface low. The stronger big time snow storm is what the EURO and its ensembles are showing and been showing consistently for the past day or so. Meanwhile the GFS is deciding to be stubborn and be more flat with the energy, weaker and further out to sea with the surface low. The UKMET is the furthest west. There is very small differences but they matter. A difference of about 50 to 100 miles is the difference of major snow storm,a glancing blow or rain getting involved on the Cape and southshore.
Right now I am leaning more to the EURO and EPS as all the other models are starting to become more inline with it. The EURO is also between the UKMET model furthest west and the GFS which is the furthest East.
EPS ensemble means with 50 ensemble members. Many to the west or over the mean. Powerful storm Furthest low-pressure members get rain into Cape Cod/South shore.
Wind will also be impressive with this system. this system looks to go through Bombogenesis which is when the pressure of low drops 24mb pressure or greater within a 24 hour period.
Strong winds are likely and look to create Blizzard conditions along the coast and east of I95.
Blizzard conditions increasingly likely for areas east of I95.Major snowfall can be expected where the heavy bands set up in eastern New England. The majority in the purple will see 12 to 18 inches but localized areas particularly in northern Rhode island and eastern Massachusetts could see pockets of 2 feet. Dry air will create a sharp cut off on the western edge of the precipitation. High snow ratio’s though could lead to rather high numbers throughout SNE. Some higher amounts are possible in the Delmarva than currently forecasted. Could also be much less and is determined by the timing of the digging trough developing into an upper-level low.
Road conditions will be bad throughout the day in eastern New England Saturday. Road crews will have a hard time keeping the roads clear. Power outages are expected especially along and east of I95. Make sure your generators are properly working, not covered in snow and away from the house. Never run a generator inside. Moderate coastal flooding is possible Saturday at the high tides. Severe beach erosion is eminent along the north and east facing coast lines.
This storm has the potential of being a record breaker it could also be nothing that big. Will get a much better idea tonight exactly how strong this system will be.
A strong storm is in the process of developing across the south today, this storm will travel northeast tonight and Sunday and make it to New England Sunday night and Monday. Those along and east of I95 will be mainly rain. Areas west of I95 snow to rain with many interior locations seeing sleet and areas of freezing rain. Areas of NW Pennsylvania, Western NY, Northern NY, Northern Vermont and the Mountains of NH and Northern Maine will see all snow, but some sleet could mix in the lower elevations.
Heaviest snowfall Northwest PA and Western NY state where 10 to 18 inches are likely with areas of up to two feet possible. The snowfall accumulations would be determined on where the heavy semi permanent banding sets up.
In the blue shaded areas 5-10 inches with the pockets of orange seeing higher amounts in the higher elevations. Sleet and valley freezing rain looks to limit snowfall accumulation.
Yellow shaded area in new England could have a situation in that the heavy precipitation is snow and sleet but by the time temperatures get to warm for frozen precipitation a large dry slot moves in shutting precipitation off Monday afternoon.
In the red shaded area. Snow to start then rain.
Green should start out as rain.
Very strong winds are expected across New England.
Wind Gusts could get as high as 85mph on the Cape and islands.
Areas along and east of I95 could see wind gusts of 50 to 60mph.
Areas north and west of I95 will see a decrease of winds of 30 to 50mph with the higher winds being in the higher elevations.
Earlier this week the Northeast had some of the coldest weather that it has seen in a while but wasn’t by any means the coldest airmass we have seen. It has since warmed a bit with highs in the 30s to low 40s regions wide today and yesterday. An Ocean storm will develop well offshore tonight and strengthen off the coast tomorrow. Rain and snow showers are possible across eastern Massachusetts, but it will most likely be restricted to the Cape and Islands. The area of high pressure over the Great lakes and the deepening area of low pressure off the coast undergoing Bombogenesis will create strong northerly winds as arctic air moves in behind a cold front Friday afternoon and Saturday night. Temperatures will drop quickly once the front passes. Low temperatures will be 5 below to 5 above Friday night into Saturday morning and with the wind wind chills will be in the range of 10 to 25 below west of I95. Highs will struggle in the single digits across most of the interior with low 10s Southeast Saturday. The cold will remain for Saturday night with lows ranging around zero.
For the Patriots at Bills game. ( Buffalo NY) Cold, Game start temperatures 8 degrees, Ending 0 Wind chills 5 to 10 below.. GO PATRIOTS!!!
Temperatures will warm a bit for Sunday as an area of high pressure shifts east setting up a complicated storm set up Sunday night into Monday night. A powerful storm is likely and currently looks to be a snow to rain situation but there remains lots of questions on storm track. Those along the coast should be prepared for coastal erosion and flooding.
Storm Discussion
A large storm is expected to impact many over the eastern two thirds of the country.
A storm will be moving into the Pacific northwest today and will shift into the Northern Rockies tonight into Friday. The energy will then shift southeast over the Rocky Mountains Friday. In the meantime a shortwave will move south/southeast over the Plains. The energy with this shortwave and 500V energy over the Rockies will interact and develop into an upper-level low somewhere in the Southern Plains Friday night or early Saturday. This upper level will spin up a surface low drawing tropical moisture from the Gulf of Mexico that will become a rather potent winter storm for the Southeast states Sunday with Rain, Ice and snow location dependent and overall track of the surface low. The further north and west of a storm track the more rain that is involved.
In general most of the models are in general agreement with this system track through Saturday with slight and marginal differences in speed and location. The EURO is a tad further South than the GFS with the upper-level low.
As this upper-level low and associated surface low starts to move east/northeast Saturday night rain, snow and Ice will develop across the southeast and Tennessee valleys.
For the Southeast there still remains a question of how much ice vs rain in the eastern Carolina’s and if there is back end snow for the Northern Gulf states as the Low pulls Northeast Saturday night/Sunday.
Locally in New England Expect snow to rain but the interior could remain freezing rain do to cold air damming. Also many of these strong storms have a comma shape to it. You have the heaviest precipitation to the west of low center and north of warm front with a large dry slot moving in between the low-pressure center and south of the warm front. So the heaviest precipitation could fall as snow and by the time the changeover starts for the interior locations of SNE the heaviest of precipitation is over. This is just a possibility but its worth watching.
Their remains uncertainty on the storm track which creates the precipitation forecast above confidence lower for the Northeast states. The further west the warmer it is over New England and the more rain. A more east track off the New England coast or over the Cape/Islands will be a snowier scenerio. These questions will become clearer Saturday when another shortwave/trough quickly moves into Canada Friday/Saturday. IT will then move over the Great lakes/ohio valley Saturday/Saturday night and will start pulling the Coastal storm in towards the coast. The timing in which this happens is important. A slower shortwave/diging trough can lead to a further South and east storm track this though is decreasing in likelyhood. A storm track over Southeast Massachusetts/Southern New England is increasingly likely.
Forecast for the Merrimack Valley.
Tonight. Partly to mostly cloudy slight chance of flurries. Lows in the mid to high 20s.
Friday. Partly cloudy. Becoming windy. Chance of snow showers. Highs in the upper 20s to low 30s. Temperatures droping into the 10s late.
Friday night. Seasonally cold. Lows 5 below to 5 above. Wind chill values as low as -25. Windy.
Saturday. Cold. Sunny highs in the high single digits to low 10s. Breezy Wind chills as low as -20.
Saturday night. Seasonally cold. Partly cloudy. Lows around 0.
Sunday. Warmer Mostly sunny. Highs in the mid 20s.
Sunday night. Becoming cloudy. Chance of snow after midnight. Snow likely around day break. Lows in the mid to high 10s.
Monday. Snow to freezing rain with a chance of rain. Ending in the mid afternoon. Highs in the low to mid 30s.
Monday night. Partly cloudy. Lows in the high 10s to low 20s.
Tuesday through Thursday. Partly cloudy highs in the upper 20s to low 30s. Lows in the high 10s to low 20s.
Its not the coldest of airmasses we have had in New England but its been a while since many across interior New England experienced sub zero temperatures for lows and single digits as daytime highs. A trough to our east is moving north/northeast today with a ridge of high pressure moving in form the Great lakes. This will provide another cold night with lows below 0 with many along the coast in the mid single digits to low 10s. Wind chills will be even cooler with windchill temperatures being as low as -15 in interior locations but wind should be rather calm as an area of high pressure moves over head. As the area of high pressure moves off the coast tonight/Wednesday a warm front will slide through with a chance of flurries. A weak rather dry cold front will move through Thursday night into Friday sending another chance of flurries or light snow showers to the region.
An ocean storm looks to develop off the east coast of the USA Thursday into Friday. A short wave moving south/southeast out of the Plains will ride along a digging trough which may or may not close off into an upper level low. This energy will then interact with the southern stream bundling up off the SE coast Thursday. This system looks to quickly develop out over the open ocean Thursday and Friday but has a slight chance of giving portions of the Cape and Islands some snow showers Friday night before moving up off the coast of Canada.
This ocean storm will help drag down another bunch of arctic cold air into the eastern third of the country setting up what could be an interesting slow-moving area of low pressure that could impact most up and down the east coast this weekend into early next week. With that said all the pieces for this system will not be over land until this weekend.
A storm system and its associated 500V energy will move onto the Washington state coast Thursday and will then travel west into the Northern Rockies where it will interact with a short wave diving south from Canada. A positively tilted trough or weak upper level low will develop with a surface low diving south over the Plain states Thursday. This trough will then likely close off if it hasn’t already Friday. This trough and associated surface low will then likely travel east/Northeast Saturday to Sunday giving a chance of a decent winter storm to the southeast states over the weekend.
There are settle but major differences in the GFS and EURO operational models. It is more than 3 days out which means there will be many changes but you can see the pieces that are needed to be watched. The GFS still shows a more amplified upper level low traveling southeast out of the plains and further north in the SE states than the EURO. The placement and timing of the high movement east out of New England and the digging through timing are also different and will greatly impact where the surface low travels once over the east coast states.
Another area of energy and trough will move over the Canadian west coast Saturday and will quickly move southeast Saturday and will try to pull the upper level low north along the coast. The speed of this interaction and placement and speed at which a high over New England/Souther Canada is will determine storm track of this system once past the southeast coast. It is just to early to determine this and this is shown on the wide spread of ensembles. If it was to impact the Mid-Atlantic to Northeast it would be in the Sunday to Monday time frame its just to early to identify impacts. We will get a better handle of this system for the East coast later this week. Until then we monitor.
Wide spread in the ensembles along with the constant flip flopping of the operational models shows the amount of uncertainty of this storm system once it reaches the SE and mid Atlantic coast. It could also be two different systems in the timeframe of Sunday through Wednesday of next week as the northern and southern stream do not interact.
Forecast for Merrimack Valley
Tonight. . Clear, chill, lows 5 below to 5 above. Wind chills as low as -15.
Wednesday. Chilly start warming in the afternoon with highs in the low to mid 30s. Partly to mostly sunny.
Wednesday night through Thursday night. Partly to mostly cloudy. Chance of flurries. Highs in the mid 30s. Lows in the 20s.
Friday. Partly to mostly cloudy. Chance of flurries. Slight chance of snow showers southeast. Highs in the low 30s. Temperatures dropping through the afternoon.
Friday night. Clear, Colder. Lows 5 below to 5 above..
Saturday. Sunny. Highs around 10 above.
Saturday night. Clear, Lows around 5 above.
Sunday. Mostly to partly sunny. Highs in the upper 10s to low 20s.
Sunday night. Becoming Cloudy. Chance of snow. Lows in the low to mid 10s
M.L.K Day. Cloudy. Chance of snow Highs in the upper 20s to low 30s.
Monay night. Cloudy. Chance of snow. lows in the high 10s to low 20s.
Tuesday. Partly cloudy. Highs in the 20s.
Tuesday night and Wednesday. Chance of snow showers. Highs in the upper 20s to low 30s.
Old man winter has awakened and is giving some areas tomorrow their first meaningful snowfall in years in the mid-Atlantic state. DC and Baltimore could see themselves ahead of Boston and NYC for snowfall come Tuesday as a positive tilted trough digs and cuts off into an upper-level low tonight with a surface low developing along it. Sending Heavy snow to Northern Virginia, Maryaland into the Delmarva tonight through tomorrow. The surface low will then slide south of New England Monday afternoon and Monday night. Nantucket could get a decent snow fall out of this but the accumulating snow will have a hard time making it anywhere pass the Islands with any accumulation being restricted to areas along the South facing coastal areas of RI and SE mass and areas east of the Cape Cod Canal due to the very dry and cold airmass that will be in place over New England along with the storm just being to far south for anything meaningful. Most across Southern New England will see clouds and that is it.
Snowfall map through Tuesday.
More energy will move over the Pacific west coast tonight sending heavy rain and snow to the Pacific northwest and northern Rockies tonight through tuesday. This energy will reconsolidate and turn into a cutoff low over the northern Plains and produce a surface low that will travel over the great lakes up into Canada producing snow or snow showers over the great lakes warming the east back up temporarily Wednesday until colder air filter ins behind it Thursday.
An other ocean storm with more energy will quickly follow the previous 500Vorticity energy producing more snow and rain for the Pacific northwest into the Rockies Wednesday. This energy along with the cold air brought in from the trough ahead of it could lead to a surface low development over the Mississpii or Ohio valleys Thursday which then transfers over off the Northeast coast late this week. There is a lot of possible outcomes, strength, does the surface low form, track etc. Until this energy moves over the Pacific Northwest Tuesday/Wednesday will will not have a solid idea on this system. My rule of not trusting a storm system to develop until all pieces of the puzzle is over the North American continent is an even more crucial this year than previous years due to model performance but the threat is there that after a while of not so much winter precipitation over the eastern third of the country, we are about to head into a more productive period for snowfall.
Forecast for the Merrimack valley ( moderate to low confidence in forecast after Wednesday due to wide spread of possible outcomes for the system later this week)
Widespread in ensemble members of the EPS but the mean or average of the ensembles does agree with the current ECMWF operational model. Confidence level will increase Tuesday.
Tonight Partly cloudy. Cool, lows in the mid to high 10s.
Monday. Cool, breezy Partly cloudy. Highs in the mid 20s.
Monday night. Becoming clear, lows in the high single digits to mid 10s.
Tuesday. Partly to mostly sunny. Highs in the high 20s to low 30s.
Tuesday night. Partly cloudy lows in the mid 20s.
Wednesday. Partly to mostly cloudy chance of rain and snow showers. Highs in the low to mid 40s.
Wednesday night. Cloudy. rain showers likely in the evening. Then Clearing. temperatures dropping into the high 20s to low 30s late.
Thursday. Clearing skies. Highs in the mid to high 30s.
Thursday night. Increasing clouds. Chance of snow late.
Friday. Cloudy. Chance of snow. Highs in the high 20s. Breezy.
Friday night. Becoming partly cloudy. Chance of snow showers. Breezy. Lows in the low to mid 10s.
Saturday. Partly cloudy. Highs in the high 20s to low 30s.
A weak quick moving clipper system will spread light snow or snow showers over the region during the morning of the 24th with up to an inch of snow possible region wide but up to 2 inches are possible in the higher elevations of the Berkshires and southern Vermont as a warm front enhances snow shower activity in these areas. This warm front will also change snow showers to rain showers on the Cape and south shore in the afternoon.
The next system which happens to move in on Christmas eve and go through Christmas. Their remains many questions on timing strength, track and therefor snow and rain lines for this system. Due to the current trends of systems in the current pattern being more progressive, I would go with a weaker faster moving system sending a mix of snow, sleet and rain to the region Christmas eve after midnight from west to east and ending in the late afternoon. Best chance of accumulating snow will be north of the mass pike. Due to guidance not performing well these past several months I will not be going into much detail with this system. A series of quick moving systems will continue next week but is to soon to determine when and what will fall with these systems.
Forecast for the Merrimack Valley.
Tonight and Thursday. Clear, much cooler. Lows in the mid to high 10s. Highs in the mid to upper 20s.
Thursday night. Increasing clouds. Snow showers or light snow likely after midnight. Lows in the high 10s. Up to an inch possible
Friday. Mostly cloudy in the morning with a chance of snow showers. Then partly cloudy with scattered flurries. Highs in the low to mid 30s. Up to an inch of snow possible.
Christmas eve. Becoming cloudy. Chance of snow after midnight. Lows in the mid 20s. Minor snow accumulation possible.
Christmas Day. Cloudy. Chance of snow, sleet and rain showers. Minor to light snow accumulation possible. Highs in the 30s.
Christmas Night. Partly to mostly cloudy. Slight chance of snow and rain showers. Lows in the mid to upper 20s.
Sunday. Partly to mostly cloudy. Chance of snow and rain Highs in the mid 30s.
Sunday night. Partly cloudy. Lows in the mid to high 10s.
Monday. Increasing clouds. Chance of snow and rain. Highs in the 30s.
Monday night. Cloudy. Chance of snow and rain in the evening. Lows in the high 20s to low 30s.
Tuesday. Partly cloudy. Highs in the 30s.
Tuesday night. Cloudy. Chance of snow, sleet and freezing rain. Lows in the high 20s.
Wednesday. Cloudy. Chance of snow, sleet and freezing rain. Highs in the 30s.
I have to give it to the NWS along with short- and long-range models at sniffing out the severe weather out break that happened over 6 states in the south and Mid-west the other night. Several of the models started to pick up the severe weather outbreak possibilities about 5 days out with the short-range picking up the severe weather spots almost to the point in which is scary accurate. Though its one severe weather event, these events in December are increasing and can indeed be linked to climate change. Tornado’s are one of several reasons why I would never live in the plains/Mid-west interior SE.
Now to the forecast.
An area of high pressure will remain over the area Tuesday. A warm front will lift north Wednesday night with a chance of light rain showers over the region. The warmest day of the week will be Thursday with highs in the high 50s to low 60s. A decaying cold front on the leading edge of a trough will move through late Thursday night and early Friday with nothing but an increase of clouds for a period. This cold front will help set up more seasonal temperatures and a possible wintery weather event for the weekend.
Forecast..
Today Mostly sunny. Highs in the mid to high 40s
Tonight. Clear, lows in the low to mid 20s
Wednesday Partly cloudy. Highs in the mid-40s.
Wednesday night Cloudy. rain showers likely. Slight chance of snow mixing in northern Merrimack Valley. Lows in the mid to high 30s.
Thursday. Cloudy. Highs in the high 50s to low 60s.
Thursday night. Cloudy, lows in the low to mid 40s.
Friday. Mostly sunny and windy, highs in the low 50s. temperatures falling late.
Friday night. Partly cloudy. Lows in the low to mid 30s
Saturday. Becoming mostly cloudy. Chance of rain and snow showers in the afternoon. Highs in the mid to high 30s.
Saturday night. Mostly cloudy. Snow likely with a chance of rain and sleet. Lows in the upper 20s to low 30s.
Sunday. Mostly to partly cloudy Chance of snow showers in the morning Highs in the 30s.
Sunday night. Clear with lows in the high 10s to low 20s.
Monday. Mostly sunny highs in the mid to upper 30s.
Long range. Some of the models are showing another system impacting the area around mid-week.
The coldest temperatures of the season has moved in to the northeast this week. Low temperatures Saturday morning will range from 15 below in the colder locations of New England to low 20s across Virginia. It will be even colder Sunday morning.
Saturday 8am temperature, Wind chills will be below zero across New England and in the single digits along the coast and the rest of the Northeast. It will be even colder for Sunday morning across New England.
This cold air will be in place for the next storm system
An upper level low will slide west into the Ohio River valley Sunday with its associated surface low. It will continue to slide eastward. It looks to weaken as it does so and open into a trough. The parent surface low will transfer its energy to a developing low pressure off the east coast along the eastern periphery of the trough.
500 vorticity showing uppler level low and trough on the left. Surface lows on the right. Do not pay attention to what its showing in terms of precipitation type and intensity with the surface map. Just look at how the parent low transfers over to a coastal low. A classic Miller B storm.
Question that becomes is how suppressed is the surface low. Upstate NY will likely not see much out of this.
Most of the northeast look to receive snow. Upstate NY state will likely not see much in terms of snow but we can not rule out some lake effect snow off of the Great Lakes when the storm starts pulling away and the upper level low reforms over or to the east of New England.
As there is alot of questions still in place with this storm, the snowfall map is vague at this time. Numbers will be put to it tomorrow.
If you are in the blue or purple based on current thoughts and guidance a moderate snowfall is forecast at this time. If you are in the purple, you could see heavy snowfall but its to early to tell where exactly the heaviest of the snow will fall. Though at this time the best bet of seeing heavy snowfall is across southeastern New England. Upstate NY state is not expected to see much in the way of snowfall with this storm system.
Merrimack Valley Weather 