Wednesday's Torch/Washout
Tuesday, January 29, 2013
Typical New England weather...one moment it's single digits and snowing, and few days later we have expected temperatures in the 50's. As I was saying before, I was expecting temperatures in the upper 40's for most a few days ago, but model guidance has only gotten stronger in terms of giving most of us temperatures in the 50's, and given the persistence of these models, and 850 mb temps, it's hard to just turn away and act like it's not there.
Both the NAM and GFS models are giving most areas in the 50's. To be more specific, Eastern MA will most likely see mid 50's, however I have a hard time agreeing with NAM and GFS saying widespread high 50's for us, but I wouldn't rule out a spotty 57F or 58F. I'll put most of RI & CT in the came category as well. As for areas west and north, I'm going with high 40's to low 50's, however I wouldn't rule out some areas (especially western areas), seeing mid 50's.
I still believe clouds and rain are going to be the deciding factor in all this, especially because it will be mostly cloudy and showers are expected later Wednesday night which will keep everything down, hence why I am being conservative with temperatures.
As for Wednesday evening/night, this frontal system that is bringing very heavy rain to the Central Plains will make its way into our area and basically give most areas a washout. Areas west of Worcester/Central CT could see at least 1" of rain. I wouldn't rule out some areas (especially NH) seeing some sort of a mix/freezing rain towards the latter end of this event. This rain should be out by Thursday morning.
Typical New England weather...one moment it's single digits and snowing, and few days later we have expected temperatures in the 50's. As I was saying before, I was expecting temperatures in the upper 40's for most a few days ago, but model guidance has only gotten stronger in terms of giving most of us temperatures in the 50's, and given the persistence of these models, and 850 mb temps, it's hard to just turn away and act like it's not there.
Both the NAM and GFS models are giving most areas in the 50's. To be more specific, Eastern MA will most likely see mid 50's, however I have a hard time agreeing with NAM and GFS saying widespread high 50's for us, but I wouldn't rule out a spotty 57F or 58F. I'll put most of RI & CT in the came category as well. As for areas west and north, I'm going with high 40's to low 50's, however I wouldn't rule out some areas (especially western areas), seeing mid 50's.
I still believe clouds and rain are going to be the deciding factor in all this, especially because it will be mostly cloudy and showers are expected later Wednesday night which will keep everything down, hence why I am being conservative with temperatures.
As for Wednesday evening/night, this frontal system that is bringing very heavy rain to the Central Plains will make its way into our area and basically give most areas a washout. Areas west of Worcester/Central CT could see at least 1" of rain. I wouldn't rule out some areas (especially NH) seeing some sort of a mix/freezing rain towards the latter end of this event. This rain should be out by Thursday morning.
Mon PM-Tue AM Snow/Mix/Rain Event UPDATE
Sunday, January 27, 2013
Here is a slightly modified forecast. I did not change much from the previous post, and left out my analysis of the models because most of you don't care about that anyways...
This event should be over before the Tuesday morning commute. We will start out as snow Monday afternoon/night, however for only a very brief time, and depending on your location you may see some rain/mix, making the commute home messy for some. There is a window of opportunity for some areas to see 2" before it turns (I'm thinking central-western MA/S NH/parts of northern CT). S NH has the best chance to cash in with this event, where I can see a possibility of 2"-3" up there. Most areas should switch over to sleet and rain/freezing rain by later on. My biggest concern is that most of this precip will freeze before the Tuesday AM commute, as surface temperatures will remain below freezing for most.
This forecast is mainly for Eastern MA, but most New England areas will not see anything significant. I expect minimal snow accumulation, if any, when this is all said and done. The accumulation totals that I am shooting for include both any snow/ice that fall.
As for what's beyond this system, we have a nice warm up on the way Wednesday, where temperatures can reach the upper 40's, and I wouldn't rule out spots of 50. There is also a storm system on the way for the end of the month which looks like a washout for most areas, with a chance of some snow towards the latter end of this system. Cold temps return later in the week.
Here is a slightly modified forecast. I did not change much from the previous post, and left out my analysis of the models because most of you don't care about that anyways...
This event should be over before the Tuesday morning commute. We will start out as snow Monday afternoon/night, however for only a very brief time, and depending on your location you may see some rain/mix, making the commute home messy for some. There is a window of opportunity for some areas to see 2" before it turns (I'm thinking central-western MA/S NH/parts of northern CT). S NH has the best chance to cash in with this event, where I can see a possibility of 2"-3" up there. Most areas should switch over to sleet and rain/freezing rain by later on. My biggest concern is that most of this precip will freeze before the Tuesday AM commute, as surface temperatures will remain below freezing for most.
This forecast is mainly for Eastern MA, but most New England areas will not see anything significant. I expect minimal snow accumulation, if any, when this is all said and done. The accumulation totals that I am shooting for include both any snow/ice that fall.
As for what's beyond this system, we have a nice warm up on the way Wednesday, where temperatures can reach the upper 40's, and I wouldn't rule out spots of 50. There is also a storm system on the way for the end of the month which looks like a washout for most areas, with a chance of some snow towards the latter end of this system. Cold temps return later in the week.
Mon PM-Tue AM Snow/Mix/Rain Event
Saturday, January 26, 2013
This event should be over before the Tuesday morning commute. We will start out as snow Monday afternoon/night, however for only a very brief time, and depending on your location you may see some rain/mix, making the commute home messy for some. There is a window of opportunity for some areas to see 2" before it turns (I'm thinking central-western MA/CT). My biggest concern is that most of this precip will freeze before the Tuesday AM commute.
This isn't a big event, so I'm not going to elaborate much more on this unless it changes drastically, such as potentially turning to an all snow event (although unlikely). This system is still a couple of days out, so some things (most likely timing) will change. This forecast is mainly for Eastern MA, but most New England areas will not see anything significant. I expect minimal snow accumulation, if any, when this is all said and done.
As for what's beyond this system, we have a nice warm up on the way Wednesday, where temperatures can reach the upper 40's, and I wouldn't rule out spots of 50. There is also a storm system on the way for the end of the month which looks like mostly a washout for most areas, with a chance of some snow towards the latter end of this system.
----------------------------------------------------------------------------------------
What the models say...
Euro
00Z (1/26) Euro shows that we may see some flakes Monday night after 7:00 PM which will then eventually turn into a wintry mix if not rain.
00Z (1/27) is showing more potential snow than the GFS, but again isn't showing much precip wise. As far as timing, it is still on line for Monday early evening.
GFS
00Z GFS is on the same track in regards to snowfall. GFS has most turning to rain/wintry mix as well but not till after midnight. Once it switches over, we may see a mix then a transition to rain, with freezing rain being a possibility for the morning commute. It will eventually turn over to just rain but will not taper out till Monday night.
18Z GFS has shifted the majority of precip N/NW, giving most of MA/RI minimal to no snow, and all mix/rain. Areas along Lake Ontario have the potential to fare the best.
00Z GFS is on the same track as 18Z in regards to snowfall amounts. Most of MA isn't even looking at 1". As far as timing, models are trending towards a Monday afternoon/evening type deal.
Ukie
On board.
GEM
This gives us more of a Euro scenario, but has us actually getting more rain/mix with this event (a lot more actually). I'm not buying into this because this model is usually unreliable in general (in my opinion and I'm sure many others), and given this far out, we can just toss it out (for now).
00Z GEM is finally in line with the GFS/Euro/NAM, but is still on the high side for overall precip.
NAM
00Z (1/27) is on queue with the other models. (NAM has lots of work to do to gain my respect back this season...let's just say it's out to lunch, and dinner.)
SREF
Still aren't biting onto the snowfall accumulation, but within the next couple runs we should get a better feel for which areas can see that potential 2" mark.
21Z run did what I expected, and is giving a 70-85% chance that most of W MA will see 2" snow. The further east you move, the less of a chance you will see that, as this disturbance is projected to move north and west of us.
This event should be over before the Tuesday morning commute. We will start out as snow Monday afternoon/night, however for only a very brief time, and depending on your location you may see some rain/mix, making the commute home messy for some. There is a window of opportunity for some areas to see 2" before it turns (I'm thinking central-western MA/CT). My biggest concern is that most of this precip will freeze before the Tuesday AM commute.
This isn't a big event, so I'm not going to elaborate much more on this unless it changes drastically, such as potentially turning to an all snow event (although unlikely). This system is still a couple of days out, so some things (most likely timing) will change. This forecast is mainly for Eastern MA, but most New England areas will not see anything significant. I expect minimal snow accumulation, if any, when this is all said and done.
As for what's beyond this system, we have a nice warm up on the way Wednesday, where temperatures can reach the upper 40's, and I wouldn't rule out spots of 50. There is also a storm system on the way for the end of the month which looks like mostly a washout for most areas, with a chance of some snow towards the latter end of this system.
----------------------------------------------------------------------------------------
What the models say...
Euro
00Z (1/26) Euro shows that we may see some flakes Monday night after 7:00 PM which will then eventually turn into a wintry mix if not rain.
00Z (1/27) is showing more potential snow than the GFS, but again isn't showing much precip wise. As far as timing, it is still on line for Monday early evening.
GFS
00Z GFS is on the same track in regards to snowfall. GFS has most turning to rain/wintry mix as well but not till after midnight. Once it switches over, we may see a mix then a transition to rain, with freezing rain being a possibility for the morning commute. It will eventually turn over to just rain but will not taper out till Monday night.
18Z GFS has shifted the majority of precip N/NW, giving most of MA/RI minimal to no snow, and all mix/rain. Areas along Lake Ontario have the potential to fare the best.
00Z GFS is on the same track as 18Z in regards to snowfall amounts. Most of MA isn't even looking at 1". As far as timing, models are trending towards a Monday afternoon/evening type deal.
Ukie
On board.
GEM
This gives us more of a Euro scenario, but has us actually getting more rain/mix with this event (a lot more actually). I'm not buying into this because this model is usually unreliable in general (in my opinion and I'm sure many others), and given this far out, we can just toss it out (for now).
00Z GEM is finally in line with the GFS/Euro/NAM, but is still on the high side for overall precip.
NAM
00Z (1/27) is on queue with the other models. (NAM has lots of work to do to gain my respect back this season...let's just say it's out to lunch, and dinner.)
SREF
Still aren't biting onto the snowfall accumulation, but within the next couple runs we should get a better feel for which areas can see that potential 2" mark.
21Z run did what I expected, and is giving a 70-85% chance that most of W MA will see 2" snow. The further east you move, the less of a chance you will see that, as this disturbance is projected to move north and west of us.
Norlun Trough Event 1/21-1/22
Friday, January 25, 2013
Earlier this week most of New England was under a Norlun tough event. Well what's a Norlun trough? A Norlun trough is one of the hardest events for meteorologists to forecast. They are known to verify either higher or lower than forecasted amounts, also known as "having high bust potential", especially in the short term. The way these troughs are set up, very narrow, heavy bands of precipitation can form, and can result in localized, and spotty, high precipitation totals (banding), while nearby regions may get very little, which makes this a tough event to forecast. These troughs tend to set up along the SE ME/ NH coast inland. Models have a hard time grasping this phenomena, mainly because they are too mesoscale (small) to handle. Because of this, models tend to under do QPF (precip) amounts for these events due to their lower resolution, so that has to be taken into consideration while making a forecast. The hardest part of forecasting this is where will this trough set up? Models will tell you one thing, but that doesn't mean it's going to set up there. When forecasting for these, sometimes it is better to look at 850-700 mb frontogenesis (VV/RH) and 700 mb analyses rather than solely relying on QPF to get a feel for where this Norlun can actually set up.
Here, you can see the progression of my forecasts with this event:
Snow for tonight is expected to begin around 7pm and should be over for most areas by 10am tomorrow. As for totals the far exterior Cape/Islands/Plymouth County/Essex County/SE NH/Southern most ME expect 4-6, although I wouldn't rule out spots of 7", which would most likely occur on the ext.Cape/Islands,Essex County/SE NH/Southern ME. Bristol County 2-3. Areas around 93 and Boston: 3-5 with spots of 6", most of Norfolk/Middlesex counties I expect widespread 2-3 but wouldn't rule out spots of 4". Worcester: 1-3, western MA: C-2", Western CT: C-2, Eastern CT 1-2, RI : 1-3.
These (Norlun trough) events are hard to pin down b/c they are boom/bust type deals when it comes to what is forecasted, and what actually falls, whether it's more or less. Basically what I am saying is that this is a low confidence forecast, but this is has potential to hit the totals above.
Following this event we'll have the Arctic air mass settling in tomorrow through Thursday. Temps for most areas in MA can range in the single digits to high teens. There's another snow event on the way for Friday night.
Short time later...
Snow's already falling...other than Essex County/SE NH/S ME/Cape/Islands I am keeping my forecast the way it is but I am leaning more towards the lower end of totals. New models keeping bulk of precip further offshore than previously modeled, which is good news for the Cape/Islands especially but Norlun trough is still progged to set up right near Essex/S NH towards tomorrow morning around 7-9 am where you'll see the heaviest bands of snow.
I ended up verifying for Cape/Islands, Bristol County, western MA, Worcester County, most of RI and CT for this event, but busted for everything else. The trough set up just a tad far offshore to prevent Essex County/S NH from getting slammed. WSI's RPM model picked up on this late on the 21st, which runs more often than commonly referred to models such as the NAM, GFS, and Euro.
Below is a picture of how the Norlun trough actually set up. Notice how far offshore it is...
Earlier this week most of New England was under a Norlun tough event. Well what's a Norlun trough? A Norlun trough is one of the hardest events for meteorologists to forecast. They are known to verify either higher or lower than forecasted amounts, also known as "having high bust potential", especially in the short term. The way these troughs are set up, very narrow, heavy bands of precipitation can form, and can result in localized, and spotty, high precipitation totals (banding), while nearby regions may get very little, which makes this a tough event to forecast. These troughs tend to set up along the SE ME/ NH coast inland. Models have a hard time grasping this phenomena, mainly because they are too mesoscale (small) to handle. Because of this, models tend to under do QPF (precip) amounts for these events due to their lower resolution, so that has to be taken into consideration while making a forecast. The hardest part of forecasting this is where will this trough set up? Models will tell you one thing, but that doesn't mean it's going to set up there. When forecasting for these, sometimes it is better to look at 850-700 mb frontogenesis (VV/RH) and 700 mb analyses rather than solely relying on QPF to get a feel for where this Norlun can actually set up.
Here, you can see the progression of my forecasts with this event:
Snow for tonight is expected to begin around 7pm and should be over for most areas by 10am tomorrow. As for totals the far exterior Cape/Islands/Plymouth County/Essex County/SE NH/Southern most ME expect 4-6, although I wouldn't rule out spots of 7", which would most likely occur on the ext.Cape/Islands,Essex County/SE NH/Southern ME. Bristol County 2-3. Areas around 93 and Boston: 3-5 with spots of 6", most of Norfolk/Middlesex counties I expect widespread 2-3 but wouldn't rule out spots of 4". Worcester: 1-3, western MA: C-2", Western CT: C-2, Eastern CT 1-2, RI : 1-3.
These (Norlun trough) events are hard to pin down b/c they are boom/bust type deals when it comes to what is forecasted, and what actually falls, whether it's more or less. Basically what I am saying is that this is a low confidence forecast, but this is has potential to hit the totals above.
Following this event we'll have the Arctic air mass settling in tomorrow through Thursday. Temps for most areas in MA can range in the single digits to high teens. There's another snow event on the way for Friday night.
Short time later...
Snow's already falling...other than Essex County/SE NH/S ME/Cape/Islands I am keeping my forecast the way it is but I am leaning more towards the lower end of totals. New models keeping bulk of precip further offshore than previously modeled, which is good news for the Cape/Islands especially but Norlun trough is still progged to set up right near Essex/S NH towards tomorrow morning around 7-9 am where you'll see the heaviest bands of snow.
I ended up verifying for Cape/Islands, Bristol County, western MA, Worcester County, most of RI and CT for this event, but busted for everything else. The trough set up just a tad far offshore to prevent Essex County/S NH from getting slammed. WSI's RPM model picked up on this late on the 21st, which runs more often than commonly referred to models such as the NAM, GFS, and Euro.
Below is a picture of how the Norlun trough actually set up. Notice how far offshore it is...
Favorable Pattern for 2nd Week in February
Friday, January 25, 2013
With a disappointing January, end of this month is "said" to look favorable. There is a system that may sweep through our area end of the month, although there is still lots of uncertainty with this system. Image below is the 500mb Height Anomaly for the second week in February. Here we are presented with a -EPO (Eastern Pacific Oscillation) and -NAO (North Atlantic Oscillation) setup, both very favorable for storm development and track.
With the -EPO, you have ridging over Alaska which allows cold, arctic air to spill into the central/northern plains, and even the northeast. This gives us the temperatures favorable for snow. With the -NAO in place, we have an area of higher height anomalies over Greenland. Since the pressure over this area is usually low, "higher" heights over this region are actually "weakening" this low pressure cell (therefore increasing the pressure). This decreases the pressure gradient between that and the Azores High, which allows cold air to meander south as well. This also causes troughing along the east coast, giving coastal storms a very favorable track.
Any coastal storm or clipper system will be favored with this setup, although with troughing so deep, we have to worry about clipper-esqe systems tracking slightly further south, and even further offshore than some may hope for, although that is just one of many possible outcomes.
With a disappointing January, end of this month is "said" to look favorable. There is a system that may sweep through our area end of the month, although there is still lots of uncertainty with this system. Image below is the 500mb Height Anomaly for the second week in February. Here we are presented with a -EPO (Eastern Pacific Oscillation) and -NAO (North Atlantic Oscillation) setup, both very favorable for storm development and track.
With the -EPO, you have ridging over Alaska which allows cold, arctic air to spill into the central/northern plains, and even the northeast. This gives us the temperatures favorable for snow. With the -NAO in place, we have an area of higher height anomalies over Greenland. Since the pressure over this area is usually low, "higher" heights over this region are actually "weakening" this low pressure cell (therefore increasing the pressure). This decreases the pressure gradient between that and the Azores High, which allows cold air to meander south as well. This also causes troughing along the east coast, giving coastal storms a very favorable track.
Any coastal storm or clipper system will be favored with this setup, although with troughing so deep, we have to worry about clipper-esqe systems tracking slightly further south, and even further offshore than some may hope for, although that is just one of many possible outcomes.
Friday Night Snow Event UPDATE
Thursday, January 24, 2013
Friday night's event looking more of a lock that it won't be more than a 2" event for even the Cape. I wouldn't rule out coastal SNE and far E MA seeing up to 2" at best as well. I expect widespread flurries with no more than a dusting to 1" and I believe some areas won't see snow at all (areas in central-western New England and NH).
It's a quick moving event, expected to start ~11 pm and be out before sunrise on Saturday for most.
Friday night's event looking more of a lock that it won't be more than a 2" event for even the Cape. I wouldn't rule out coastal SNE and far E MA seeing up to 2" at best as well. I expect widespread flurries with no more than a dusting to 1" and I believe some areas won't see snow at all (areas in central-western New England and NH).
It's a quick moving event, expected to start ~11 pm and be out before sunrise on Saturday for most.
Friday Night Snow Event
Thursday, January 24, 2013
So I've been getting asked a lot, what's the deal for the snow Friday night into Saturday morning. Right now it isn't looking as good (snow wise) than it did a few days ago. As models are still trying to sort their differences, it is looking like a C-2" event for eastern MA, with 3"-6" chance for the far SE MA/Cape/Islands at best. Again, a lot can change, especially if models bring this system further NW, which would result in widespread snowfall, and respectable accumulation totals, but I'd put that at a low probability right now. Stay tuned and continue enjoying this arctic/polar air depending on where you are.
So I've been getting asked a lot, what's the deal for the snow Friday night into Saturday morning. Right now it isn't looking as good (snow wise) than it did a few days ago. As models are still trying to sort their differences, it is looking like a C-2" event for eastern MA, with 3"-6" chance for the far SE MA/Cape/Islands at best. Again, a lot can change, especially if models bring this system further NW, which would result in widespread snowfall, and respectable accumulation totals, but I'd put that at a low probability right now. Stay tuned and continue enjoying this arctic/polar air depending on where you are.