Although yesterday’s forecasted thunderstorms never came to fruition here in Southern New England, they did occur back in Pennsylvania and New York. There were 2 confirmed tornadoes; one in Elmira, New York and the other just to the southeast across the border in Pennsylvania. Perhaps the most impressive feature from yesterday was the bow echo that formed along the northern extent of the severe weather. Which had radar estimated straight line wind speeds of 80-90 mph. Official observed wind gusts of 60-65 mph associated with that bow echo came from a team of UMASS Lowell storm chasers that were stationed in Newbourgh, New York.
As the potent bow echo entered Southern New England however, it ran out of steam. Post-analysis appears to reveal that it entered into a less favorable environment for maintaining the strength of such a system. When it entered Connecticut, it appears that the bow echo entered an environment with higher values of Convective Inhibition (CIN); which were found when analyzing the balloon soundings from OKX and CHH from 00Z (8 pm) yesterday.
After failing on so many levels with yesterday’s forecast, I was very frustrated and angered with how inaccurate I ended up being. So I did a little post-analysis of myself and I have come away with a lesson learned. I bought into the hype surrounding yesterday’s event. I forgot to use common sense; which for here in New England is that events like yesterday’s forecast, just don’t happen. Only on rare occasions (once every 10-15 years or so) do such events occur.
But enough of my rant about yesterday, on to the forecast at hand. As the title says above, we look to have some unsettled weather coming up for really the entire 7 day forecast.
Looking at the big picture, the continental pattern so to say, we are heading for such a pattern that will keep us under the effects of an upper level trough. The pattern is almost an omega block, but it isn’t fully one. In an omega block, there are 3 main features, a big central area of High Pressure; flanked on either side by a cut-off area of Low Pressure. For the upcoming pattern, there is going to be a big central area of High Pressure located over the Oklahoma/Texas panhandle region. But on either coast, there are no cut-off lows. Instead of cut-off lows, we basically get just a trough that will allow for pieces of energy to dive down out of Canada through the Great Lakes and out south of New England. For a much clearer picture of what I mean by the upcoming pattern, see image below. Forgive me, my paint writing skills are a work in progress.
Now that we have discussed the upcoming pattern; one in which it appears we will be unable to rid ourselves of through at least next weekend, let’s talk some finer details. Yes we will be in an unsettled pattern, but this isn’t to say that our entire week will be a washout. The majority of the forecast should be mainly dry and there will be times when the sun is out and the weather is relatively nice. What I am really trying to get across is that at any moment during the week, the chance for a shower or thunderstorm exists.
7 DAY FORECAST
Tonight… Partly cloudy skies. Humid. As both the overnight lows and dew point will be at or just above 60. General rule of thumb, with air temperature and dew point so close, areas of patchy fog can develop.
Tomorrow… Everyone has a chance of a shower or thunderstorm. Best chance however lies in New Hampshire, Southern Vermont and Western Mass. Highs around 80.
Tomorrow Night… Shower threat diminishes with loss of insolation (daytime heating). Lows around 65. Again watch out for patchy fog.
Sunday… Really a repeat of Saturday except that temperatures will be around 75 and not 80. Chance of showers for all, best chance with places mentioned above.
Monday… Probably the best day of the week. Still chance of a shower for Vermont and Western Mass. Highs in the upper 70s.
Tuesday… Chance of a shower or storm for all of Southern New England. Highs in the upper 70s.
Wednesday-Friday… Chance of shower or storm for Western and Central New England (VT, NH, W. MA, CT). Highs at 80 or slightly above.
-Chris
The following are from the Storm Prediction Center’s Day 1 outlook.
The first image is their Categorical Outlook where they assign a risk assessment to the chances of severe thunderstorms. The categories are: “Thunderstorm”, “Slight”, “Moderate”, and “High”. As you can see from the image below, all of us are in the “slight” category, while all of western Southern New England falls under the “moderate” category. Interesting to note, overnight SPC extended the coverage of the “moderate” to the north and east a bit. For those wondering what a “High” risk day is, the April Super Outbreak from last year was a “High” risk day.
This image is of the SPC’s tornado outlook for today. This shows what they feel are the probabilities of a tornado occurring. As you can see, all of Southern New England has a 2% probability, but those same portions of western SNE have a 5% probability.
As I said yesterday, the primary threat is going to be wind damage. This image below shows the probability of wind damage. All of SNE has a 30% chance of seeing wind damage, while those same western areas have a 45% hatched probability. Again the hatched region means that there is an increased likelihood of it occurring. We don’t see probabilities like this around here very often.
Finally, this is the hail probability forecast. Less likely than receiving wind damage, but still not unlikely as any strong to severe thunderstorm has the possibility of producing hail. All of SNE has a 15% chance, while again those same western areas have a 30% chance. 
Probability charts like these don’t come along very often for our neck of the woods, so these will definitely be going into the archive. Whether it be for how accurate they are or for how incredibly wrong they are; only time will tell.\
Again, I will be doing my best to keep everyone up to date via facebook or Twitter. So find me and follow me @Chrisrotary12.
-Chris
Well this is certainly something that we don’t see very often. The Storm Prediction Center (SPC) has put portions of Southern New England (SNE) under a “moderate” risk in their day 2 outlook. The first image shows the location that all of Southern New England is under a “Slight” risk, while western CT and SW MA are in the “moderate” threat region. The second image shows SPC’s Probabilistic forecast. All of SNE is being given a 15% chance of severe weather, but most of SNE is being given a 30% chance with some portions receiving a 45% chance. In addition, SPC has added the hatching in with the shading. What this means is that they are highlighting these areas for increased potential. So basically, all of SNE has an increased potential for severe weather tomorrow.
The following is taken directly from the SPC’s latest Day 2 outlook:
A RELATIVELY NARROW CORRIDOR OF ENHANCED TORNADO RISK SHOULD DEVELOP
ALONG THE WARM FRONTAL ZONE WHERE EFFECTIVE SRH AND STRONGEST
DEEP-LAYER SHEAR WILL BE MAXIMIZED. ALTHOUGH PINPOINTING THIS
CORRIDOR IS DIFFICULT GIVEN LIKELIHOOD OF PRECEDING OVERNIGHT
CONVECTION…IT APPEARS MOST PROBABLE FROM PARTS OF NY INTO SRN NEW
ENGLAND. SOME CONVECTION-ALLOWING GUIDANCE SUGGESTS THAT DISCRETE
CONVECTION MAY FORM WITHIN A PERSISTING WAA REGIME THU AFTERNOON.
What the above statement from SPC says in simple terms is this: Where ever the warm front ends up tomorrow, places with in the vacinity of the warm front will have the best chance at seeing a tornado occur. Tomorrows forecast basically all hinges on where the warm front locates itself. Forecasting this though is going to be very tricky. As it stands now, the front looks to progress to along the MA/CT border, BUT computer guidance has slowly been creeping north. If front made it to MA/NH border by 8 pm tomorrow, this would not be shocking to me. As for the dangers tomorrow, damaging hail, damaging winds, and possibly an isolated tornado. All of SNE should be on the lookout.
The image above is the same as the one I posted yesterday. This is the Significant Tornado Parameter from the SPC SREF valid for 8 pm tomorrow evening. Values greater than 1 indicate that there is an enhanced risk of a tornado. Here there are values over 2 for a lot of SNE. Yes, the values have risen, but they have also expanded northward. A trend that will have to be monitored heading into tomorrow morning.
When looking at tomorrow, there are a bunch of different parameters that one such as myself will look at. Those include: CAPE, CIN, SRH (storm relative helicity), Shear, 850 mb winds, LLJs (low level jets). You think of it, there is probably a parameter for it. Right now all of the parameters seem to be in place. A few may be slightly off timing wise, but they are sufficiently high enough (or low enough) for severe weather to occur. Right now, all we can do is basically sit back and wait to see if what the computer models are showing will happen.
At this instance, convection is going nuts in Michigan. This convection looks to continue to hold together through the night and make its way into SNE. If by 3 or 4 am some of us are awaken by the sound of rain or thunder, this would not be surprising. But I am expecting that we will feel the effects of a dying system. Once we rid ourselves of the Great Lakes leftovers, the sun should come out and set the stage for the afternoon show. Initially storms should start out isolated in nature, allowing for them to possibly take on supercell-like characteristics. Then as the day progresses, more and more storms will form eventually forming bowing segments with associated damaging winds. Basically…..tomorrow is going to be a long and eventful day. Stay alert.
First thing that we need to keep an eye on is cloud cover tomorrow morning. If we wake up and the sun is shining and warming up the low levels of the atmosphere, then game on.
I will be at my internship tomorrow at NECN with Matt Noyes, I will be doing my best to keep everyone updated via facebook or twitter. (@Chrisrotary12)
Too excited about tomorrow to possibly make a full 7 day forecast, but looking forward, there is a chance of thunderstorms again on Friday and Saturday. Nice weather for Sunday and Monday. Then possibly unsettled for Tuesday and Wednesday.
-Chris
Tomorrow is going to be beautiful, so let’s skip it. Thursday looks very interesting with regards to severe weather. The Storm Prediction Center is highlighting us with a “Slight” risk already. The set-up on Thursday is as follows. During the morning, a warm front will push up from the south into Southern New England. The placement of the warm front is key to Thursday’s potential. Those of us who end up south of the warm front will have the best chance at seeing severe weather; those who end up on the north side of the front have the best chance at seeing some decent rains.
On the morning of Thursday, there is the possibility that a MCS could ride along the warm front and through portions of Southern New England. MCS stands for Mesoscale Convective System. Simply put it is a large cluster of thunderstorms that bring with it the potential for severe weather that last for a prolonged periods of time and cover great distances. This looks to be our first show of the day.
Next up to the plate is the arrival of the Cold Front. Those of us that get into the warm sector will wait for the Cold Front to come and be the forcing mechanism that sparks off more thunderstorms. Some of these thunderstorms have the chance to take on some supercell characteristics. Meaning damaging winds, large hail and possibly even tornadoes. There I said it, at this very moment, Thursday looks like it has the possibility to produce a tornado.
The image above is from the Storm Prediction Centers SREF model. The parameter that I have chosen to show is the Significant Tornado Parameter. Values higher than 1 highlight an increased risk for tornadoes. This image above is for 5 pm on Thursday. And it is showing values of 2 for portions of CT.
Now, we have to remember that we do live in New England, so an event that produces a tornado is unlikely. All I am saying is that the set-up appears to show the possibility of a tornado.
As I said above, the position of the warm front is everything. And right now, model guidance is kind of all over the place with the position of the warm front on Thursday. I suspect that the front will be able to push into at least the Southern Half of Southern New England, but if it pushed itself to a position along the MA/NH & VT border that would not be shocking. This also coincides with what the Storm Prediction Center is thinking because they are highlighting all but eastern portions of Southern New England.
Right now, it looks like all of Southern New England has an increased chance of severe weather for Thursday. But again we have to remember, this is New England, which means that a lot of things could go wrong (and probably will).
But as a rule of thumb for New England severe weather, if we want a sneak peak for what we might be in for, keep an eye on Michigan for tomorrow. Many of our best severe weather events have been preluded by a severe weather outbreak in Michigan. So I know that I will be watching what unfolds around the Great Lakes.
7 DAY FORECAST:
Tonight: Passing clouds and chance of a stray shower or rumble of thunder. Lows around 60.
Wednesday: Beautiful. Lots of sun and highs in the low 80s.
Thursday: See everything mentioned above. Chance of thunder in morning. Then again in afternoon. Some storms could be severe. Highs around 80.
Friday: Chance of a thunderstorm. Highs around 80.
Saturday-Tuesday: Shaping up to be a nice weekend. Isolated chance of a thunderstorm on Saturday. Highs in the low 80s.
-Chris
Well I am glad to see that the Cold Front for today and tomorrow has behaved as I thought it would. Thunderstorms have struggled to move into portions of New England. The state of Vermont appears to be the only location in New England to experience a thunderstorm. Looking ahead to tomorrow, the Cold Front will be positioned right through the heart of Southern New England by the morning. Which is why I am putting in the chance of a shower for the morning forecast. But as the day progresses, so will the Cold Front; which will push offshore sometime in the afternoon or early evening. Meaning that most of us should be spared from having their afternoon ruined by a shower or thunderstorm. I can’t totally rule out a thunderstorm for far eastern portions of Southern New England during the afternoon, but if nothing were to occur it would not be surprising. Looking ahead to the rest of the week, Wednesday should be a beautiful day, while on the day Thursday we will most likely be watching as a batch of rain approaches us from the southwest. Looks as if the rain gets in here late on the day Thursday and sticks around through the overnight. Then we look to be shaping up for a pleasant weekend.
7 DAY FORECAST:
Tonight: Passing clouds and chance of a stray shower or rumble of thunder. Lows around 70.
Tomorrow: Warm. Highs in the mid to upper 80s. Chance of a shower in the morning, then isolated chance of a thunderstorm in the afternoon.
Wednesday: Beautiful. Lots of sun and highs in the upper 70s.
Thursday: Increasing clouds throughout the day. Chance of a rain or thunder towards the evening. Highs around 80. There is a chance that the overnight could turn into an all night soaker.
Friday: Clearing takes place giving way to a nice day. Highs around 80.
Saturday-Monday: Shaping up to be a nice weekend. Highs around 80.
-Chris
Expect a quiet to the weekend as tomorrow will feature highs in the low 80s and not much else. Monday and Tuesday are a rather interesting forecast though. There is a cold front that will be approaching New England from the Northwest, but the timing of the front should be interesting.
Right now it appears that the timing will be such that Eastern portions of New England may miss out on the chance for good thunderstorms. On Monday afternoon and evening the position of the front will allow for thunderstorms to enter Western portions of New England; then slide east as the night progresses. Still a couple of days away, but portions of Western CT and Western MA looked to have a chance at a few stronger storms. As any convection that enters New England Monday evening slides east, expect it to weaken as night falls.
Then on Tuesday, the cold front will have moved into New England and by Tuesday morning it should basically be right in our neighborhood. Meaning that we could potentially miss out on a chance of thunderstorms on Tuesday because the front will be through the area before we have a chance to warm up the atmosphere. Right now though I will say that even though the front’s location will prevent us from any really exciting weather, there is definitely a chance of a shower or storm on Tuesday.
As is always the case with forecasting the weather, a forecast is subject to change. Especially one like this that deals with the timing of a frontal passage. Speed the front up by a few hours and Monday could be exciting for all. Or slow the front down for a few hours and Tuesday could become exciting.
7 DAY FORECAST
Tonight: Clear skies with lows around 60. For anyone who was out around 850 pm, it was a beautiful sunset.
Tomorrow: Mostly sunny. Highs in the low 80s.
Monday: Chance of a late day shower or storm; especially in western New England. Chance of an overnight shower or storm for all. Highs in the mid 80s.
Tuesday: Chance of a shower or storm. Highs in the mid 80s.
Wednesday & Thursday: Mostly sunny. Highs around 80.
Friday: Chance of a shower or storm. Highs in the upper 70s.
-Chris
Yesterday I mentioned that the south coast would have a chance of a shower for today. Well it turns out that the “chance of a shower” turned into a full on rainy day. Oops. Currently the states of CT and RI are socked in by rain. Which is giving the rest of us the blanket of cloud cover that we are experiencing. The rain shield should slide to the east or even almost east-southeast. Meaning that SE MA and the Cape can expect some rain at some point today. The rest of us can just expect the clouds.
Good news to report is that this weekend looks amazing. Saturday and Sunday are going to be pristine and very comfortable. With highs in the upper 70s to low 80s; with dew points in the 50s. Just perfect. The only chance of precipitation we have this weekend appears to lie in Northwestern portions of New England and that is late in the day on Sunday.
Looking ahead to next week, Monday and Tuesday should feature the chance for showers and thunderstorms. But the rest of the week after that appears dry with highs in the low to mid 80s. So all in all not that bad a stretch of weather. Enjoy.
7 DAY FORECAST
Today: Rain across the southern half of Southern New England sliding east towards SE MA and Cape Cod. Mostly cloudy for everyone else. Highs in the mid 60s for those getting rain now; mid 70s for those who stay dry. East-northeast wind 0-5 mph.
Tonight: Rain moves offshore and skies gradually clear. Cool. Lows in the mid 50s.
Tomorrow: Very nice. Highs in the upper 70s. South wind 5-10 mph.
Sunday: Chance of a late day shower or storm for Northwestern portions of New England. Meaning that the rest of us experience another perfect day. Highs in the low 80s. South-southwest wind 5-10 mph.
Monday: Chance of showers and storms. Highs in the low 80s. South wind 5-10 mph.
Tuesday: Chance of showers and storms. Highs in the low 80s.
Wednesday: Partly cloudy. Highs around 80.
Thursday: A bit warmer. Highs around 85.
-Chris
Boy yesterday was fun huh? The image above shows the severe weather reports that have been submitted to the National Weather Service. The most impressive thunderstorm of the day ended up being the first thunderstorm of the day. It originated along the MA/NH border and moved ESE through Lowell and eventually offshore through the Lynn area. This thunderstorm was the one responsible for the tornado warning that was issued for the Lynn and Saugus areas.
What was amazing about this storm was how it interacted with what is known as the seabreeze front. Typically a seabreeze will kill any convection that it interacts with, but yesterday’s actually helped to intensify any storms that converged with it. What the front did was increase the amount of shear in the environment that the storm was feeding off of. By increasing the amount of shear, this allowed the storm to better organize itself and take on characteristics of a supercell. This allowed the storm to look like the thunderstorms that are seen out in the midwest, not New England.
But now that yesterday is behind us, we have a beautiful stretch of weather to look forward too. There isn’t a single high temperature in my forecast that is higher than 85. Combine that with the occasional shower or thunderstorm and that makes one great forecast!!
7 DAY FORECAST
Today: Leftover clouds from yesterdays cold front that are currently draped across CT, RI, SE MA and the CAPE will move offshore. Giving way to the sunshine that the rest of us are experiencing. Today’s high right around 80. Combine that with dew points in the low 50s and it is perfect outside. Great day to go play some golf.
Tonight: Mostly clear skies making for a nice evening. Lows around 60.
Tomorrow: Cooler. Partly cloudy. Highs 70-75. Chance of a shower along the South Coast.
Saturday: Sunny with highs in the upper 80s.
Sunday: Running out of ways to say it is going to be nice outside. Highs in the low 80s.
Monday: Highs 80-85. Chance of a late day shower or thunderstorm. Mainly for the western half of New England.
Tuesday: Highs in the low 80s. Chance of an afternoon shower or thunderstorm.
Wednesday: Back to saying how nice it is going to be. Highs around 80.
-Chris
So the best way for me to illustrate to you what is going on today is well…..to illustrate it. So I drew this map.
The current position of the Cold Front, determined by satellite images is depicted above in the blue.
The area outlined by GREEN are the locations that hold the potential for thunderstorm activity to initiate within the next couple of hours.
The area outlined by RED are the locations that have the potential for thunderstorms later on the afternoon as the Cold Front drops south.
The area outlined by PURPLE are the locations that I feel have the best chance at seeing strong to severe storms. My reasoning for this is such: These locations will have sufficient day time heating. They currently hold the highest CAPE values. And they also have the best lapse rates. But please don’t get me wrong, I believe that any location outlined on the map has a chance, I just like those counties outlined by purple better.
Today’s main threat is going to be damaging winds. But with all severe thunderstorms, damaging hail and an isolated tornado are always possible.
Throughout the afternoon I will be here posting updates of the days events. You can also follow me on Twitter @Chrisrotary12
-Chris
Relief is on the way tomorrow evening. A cold front that is just making its way into parts of Northern New England will be crossing through Southern New England tomorrow. I am still confident in the finer details that I laid out a couple of days ago. The only thing that has changed is the potential strength in any storms that form tomorrow afternoon. As you can see from the image posted with this blog, the Storm Prediction Center is forecasting a 30% chance of severe storms for most of Southern New England tomorrow.
As I said a couple days ago, tomorrow should break down as follows. The cold front should be located in Southern New Hampshire and Vermont by tomorrow morning. Meaning that Northern New England will be allowed to enjoy a beautiful day. By early afternoon, the cold front should be located just south of the Mass/New Hampshire border. Allowing for day time temperatures to reach up into the upper 80s for most, possibly low 90s for parts of Connecticut and Rhode Island. The atmosphere will have sufficient time to destabilize and showers and thunderstorms should be forming by about 2 pm. Some storms can and will be strong to severe producing damaging winds and hail.
By saying “the atmosphere will have sufficient time to destabilize”; what I mean is this: Simply put, when looking at how unstable the atmosphere is, there are two parameters that can be looked at. (Yes there are many many more, but a broad forecast can be made off of just two) They are what is known as CAPE and CIN. CAPE = Convective Available Potential Energy. Simply put, it is the amount of energy that a parcel of air would have if lifted a certain height into the atmosphere. CIN = Convective Inhibition. Which is just the opposite of CAPE. It is the amount of energy in the atmosphere that is trying to prevent the same air parcel from rising.
For tomorrow afternoon, as the surface temperatures increase, so will the amount of CAPE. By the afternoon, most places south of the Mass Pike will have CAPE values of over 2000 J/kg. Which is more than enough to support thunderstorms and potentially strong ones. Also by tomorrow afternoon, CIN values for most of the same areas will be decreasing towards 0. Setting the stage for widespread thunderstorms.
Finally by taking a look at what the storms have produced in Northern New England today, it would appear that damaging winds will be our main threat. So, just keep a eye to the sky during the afternoon hours tomorrow.
By Thursday morning, the front has cleared the south coast and we usher in the return of some much more bearable weather as highs to finish out the week will hover around 80. Our next chance of precipitation after Wednesday isn’t until Sunday afternoon.
7 DAY FORECAST
Tonight: Hot and sticky, overnight “lows” around 75. Air conditioning working overtime tonight.
Tomorrow: Warm; highs in the upper 80s for most, low 90s for some. Chance of strong thunderstorms. Particularly south of the Mass Pike. Some storms could produce damaging winds and hail.
Tomorrow Night: Storms end and cold front moves offshore. Lows in the upper 60s to around 70.
Thursday through Saturday: Beautiful. Highs around 80. No complaints here.
Sunday: Chance of a late day thunderstorm. Highs in the low 80s.
Monday: Chance of a shower or storm. Highs in the mid 80s.
-Chris
Chris Hampton Weather 