When will this weather pattern change?

[hilltopper]

Originally Posted by meteotrade

-Concord has had more heating degree days than cooling degree days. In other words, it's more likely that you would have used your fireplace this summer than your A/C.

I know Heating Degree Days are firgured using a base temperature of 65º F. How are Cooling Degree Days calculated?

[meteotrade]

Originally Posted by hilltopper

I know Heating Degree Days are firgured using a base temperature of 65º F. How are Cooling Degree Days calculated?

Same way... a degree day is just a departure of the mean temp from 65. Yesterday the mean temp in Concord was 67, so there were 2 cooling degree days.

[meteotrade]

And incidentally, congrats if you picked next week as your vaca week. Once we get beyond Friday (which is probably a raw day) we should get into a warmer and more humid pattern through at least the middle of the week... dare I say, above normal temps? Of course the t-storm chances will be ever present but that's a small price to pay for warmth.

The one caveat: We are extremely vulnerable over the next couple weeks to the tropics thanks to a "coconut connection". In other words, our winds aloft are due south all the way to Cuba which will transport not only the warm, humid air up the coast but anything storm related that decides to develop.

[AC2717]

a glimpse into the future of what might come this hurricane season???

[Resident 2B]

Originally Posted by meteotrade

The one caveat: We are extremely vulnerable over the next couple weeks to the tropics thanks to a "coconut connection". In other words, our winds aloft are due south all the way to Cuba which will transport not only the warm, humid air up the coast but anything storm related that decides to develop.

Looking at the satellite and the models and reading several Forecast Discussions plus the TPC discussions, there looks to be something semi-tropical trying to get together north of the Bahamas to southeast of Cape Hatteras. Even the NWS/TPC thinking does not seem to be aligned completely, but the clouds are there and the water vapor imagery shows a lot of wet air.

The models are all over the place regarding what might happen if something forms. However, as meteotrade has pointed out in yesterday's post, the flow from the south is developing and looks to be on the increase.

I am not saying we will get a tropical storm, but we could get some heavy downpours Thursday night into late Friday. It could be more interesting on Cape Cod.

This is finally something somewhat exciting, weatherwise.

R2B

[meteotrade]

Originally Posted by Resident 2B

Looking at the satellite and the models and reading several Forecast Discussions plus the TPC discussions, there looks to be something semi-tropical trying to get together north of the Bahamas to southeast of Cape Hatteras.

Yep, it certainly looks interesting doesn't it? My personal feeling is that it is more "sub" tropical in nature, but in the end I don't think it matters. I agree, we are going to get whacked with downpours tonight... this may be a replay of a few weeks ago when we had big overnight flooding in southern New England but this time NH may be included as well.

[Resident 2B]

The system is now officially sub-tropical, identified as "Invest 98L".

My personal opinion is the local NWS forecast is underplaying the rain amount for the lakes region a bit. I think it will be 1.5 inches or so in the next 30 hours, perhaps more. Not much wind here, just waves of downpours.

Track is still a bit up-in-the-air, but it looks like it will pass between Boston and the 40/70 benchmark, most likely right over the Cape.

R2B

[CanisLupusArctos]

The low pressure responsible for today's rainstorm has been reminding me of the Blizzard of '78 - at least on the weathermap. Low pressure forming near Florida, bringing a great deal of moisture up the east coast, with cold air from Canada trying to move down at the same time. No storms look exactly the same, but I definitely saw the similarities between today's rainstorm and a situation that us snowlovers pray for, come February. These nor'easters are definitely much more common in winter than in summer, and we've had at least a couple of them this summer.

The rain is almost over. The back edge of it is moving from SW to NE, and most of Massachusetts is now beginning to dry out. We've had just over an inch of rain at Black Cat, which would've been 10-15 inches of snow, maybe 20 if it was cold enough. For the afternoon expect this steady rain to taper off to occasional showers or drizzle (which would've been 'flurries' in winter) but otherwise just cloudy (the part where we all would've gone out to shovel/snowblow/plow.)

Tropical season... I think it's going to be a quiet season. It's been quiet so far. The pattern has favored wintertime features more often than not, this summer. There are many reasons this affects hurricane development. It goes beyond a simple temperature equation. Hurricanes don't need 'just heat.' They are a mix of hot and cold, and the weather around them needs to be just right. For as powerful as they are, they are still very sensitive to things like headwinds and dry air. If dry air pours off the edge of the continent (part of a wintertime pattern) tropical development is probably not going to happen. Wintertime winds over the tropics follow different courses than summertime winds, and this also dictates hurricane development. There are favorable and unfavorable courses. Even the most powerful hurricane can lose a lot of strength when it meets with unfavorable winds. Its circulation may be powerful, but it's delicate and doesn't like to be jostled by outside conditions. Having said all the above, I don't think it will be an active hurricane season because the weathermap has been filled with wintertime features this summer. Disclaimer: It only takes one hurricane and "just the right steering currents" to make a memorable season. Andrew was the first storm of its season, and that happened in August.

Some are asking, "Why all the hot air in places like the Pacific Northwest, if we're in a wintertime pattern?" Because weather is physics on a very large scale. In summer, the warm air wants to occupy the northern hemisphere evenly, and if it did, we'd be able to predict temperature based on latitude alone. But that's not the case. The earth doesn't heat or cool evenly. That leaves warm and cold air masses. The cold ones are the heavier of the two. Warm air doesn't actually rise - cold air falls because it's heavier. Nothing on earth rises, because gravity is always here. There is warm, and there is cold. One is heavier than the other (cold). Gravity pulls the heavier object to the ground, and displacement forces the lighter object to go somewhere else. Air masses are invisible objects: They bash into each other, one can crush another against a third, and stuff like that.

Perhaps you have noticed, especially in wintertime, that when we in the east are very cold, it's usually warm out west. The cold air masses move southeast from Canada and New England is in the direct path. When the cold air moves southward into warmer territory, the warm air must go somewhere. It may have to go where it normally doesn't want to. Think of it in the same way as when a person canonballs into the lake. Water comes flying UP, above the surface, and for a while the air is filled with blobs of water. That is not a normal situation, but it settles back down again. However, if a steady stream of people continuously jump off the end of the dock, the air in that vicinity will become repeatedly filled with blobs of water. The cold air masses are like people cannonballing themselves off the end of the dock. New England has been where they've been landing all summer long. The warm air ("water") has been splashing up in other locations. It is not as likely that the west coast would get the same cold air masses, because the polar air masses want to move southeastward, and the west coast doesn't have a continent to the northwest. It's a huge ocean. Cold air masses don't stay cold for very long over oceans.

The pattern we've been in all summer would generate a great deal of snow around here in wintertime, and our friends out west would be saying "Where's all the snow?" It happened that way during the winter of 2007-08 when we had all the roof collapses in this area. My friends out west were booking their ski vacations here.

I have seen some info within the last couple days that suggests the larger scale "climatological autumn" got started in early July. This would not surprise me. If true, it would mean that summer gave up, only two weeks after the days peaked in length and started getting shorter again ("First day of summer.") Normally the large-scale climatological autumn gets started in early to mid August. That is when we typically see our first puff of cold/dry air from the northwest. For those of you who were here on July 5, you may remember it looked and felt like "after Labor Day." Typically we do get summer weather after the onset of fall, so summer weather will continue to occur, but I think we're at the peak of it now.

Enjoy whatever we get during the next couple of weeks. It will probably be marked by a great deal of meteorological battle as the cold air remains nearby and is not showing any signs of leaving the warm air alone here.

Eventually, autumn will become dominant, and that will push the battle zone back to our south. That will clear us out. The colder, drier air from the continent will take over again, as we had in April. It might even give us another 90-degree day. If you remember, those 90-degree days in April were not humid ones. It was a continental, not tropical, air mass. Without much humidity (water) in the air to help regulate its temperature, the air was able to change temperature quickly as it does in the desert. When the wind started blowing in from the west, it forced the air to descend in elevation from the inland mountains to the coast. When air descends quickly its pressure increases, and it heats up. The opposite is also true: A can of compressed air will actually get frosty if you discharge it all at once, because the contents inside are rapidly losing pressure. If you ride a fast train through a deep tunnel, you'll notice the air inside starts to get very warm as you reach the lowest part of the tunnel. That's temperature changing in response to a pressure change, and it's much more likely to happen with dry air than with humid air. Therefore we may get another 90-degree day as soon as autumn boots out all this moisture.

Water temperature note: The water temp monitor at the WeatherCam has been replaced by Sensatronics at their own expense. This is a plug for them. They have been great supporters of the WeatherCam over the past couple of years.

[granitebox]

Thanks for working to get the water temperature gauge back up and running.

That is one of the first things I look at while not at the but the kids are there out at camp.

[jerseyonbear]

Arriving this weekend for my 2 weeks and would love to see the sun and nice temperatures. Would hate to be closed up in the house with 4 young ones. So my forum friends please start the sun dance!!! Thanks

[Skip]

Thanks CLA, very interesting and informative read, as usual!

What really piqued my curiosity was the observation that we may have entered "autumn" several weeks ago.

For at least two weeks now while travelling the seacoast and foraying further north alongside the western spine of Winni up to Tilton I have noticed a peculiar thing. Scattered about roadside, but particularly prevalent in swampy areas, I have observed many young Maple trees with a tinge or full bloom of early fall red leaves!

I know that this can be brought on by various forms of environmental stress, but is this a sign of things to come in but a few short weeks?

Anyone else notice this phenomenon?

[chipj29]

Originally Posted by Skip

Thanks CLA, very interesting and informative read, as usual!

What really piqued my curiosity was the observation that we may have entered "autumn" several weeks ago.

For at least two weeks now while travelling the seacoast and foraying further north alongside the western spine of Winni up to Tilton I have noticed a peculiar thing. Scattered about roadside, but particularly prevalent in swampy areas, I have observed many young Maple trees with a tinge or full bloom of early fall red leaves!

I know that this can be brought on by various forms of environmental stress, but is this a sign of things to come in but a few short weeks?

Anyone else notice this phenomenon?

I noticed the same thing up in the Ossippee area of Rt 16/25 just yesterday. I have noticed even down here in the Concord area some maples have reddish tips on the newest growth for most of the summer. I think it is more indicitive of the amount of rain we have had, as opposed to an real early fall. Hopefully we will get some warmth in the next couple of weeks to keep the early autumn at bay. Barring a real heat wave, it is my belief we will have a somewhat early autumn. I also believe that September and October are going to be unseasonably warm. But don't quote me on that, look at how good (not!) my predicition was earlier in this thread.

[SIKSUKR]

Stayed at my skihouse in Franconia this weekend and noticed the same maples changing. I believe those are swamp maples as I have one at my house in Bedford that starts changing every year in mid August. It has some red edges already.

[CanisLupusArctos]

I found this leaf underneath a maple on the Moultonborough Neck Road yesterday. It wasn't the only one. The second picture is of a sunset I photographed from the bleachers at Fenway Park on July 9. I'll talk about that in a minute.

Chipj29, you may be right about the unseasonably warm autumn. We have an El Nino going in the Pacific right now. That often spells cool wet summers and warm dry winters for us. It was an early El Nino though, which means it may be early to end. We may remember that winter of 2006-07 got off to a chilly, early start. Then it became warm and rainy for a while, right into January. Then, the El Nino broke down and suddenly we went into the icebox for the rest of the season - we had a mild Christmas and a white Easter.

We could very well have a mild autumn until that El Nino breaks down. Then watch out.

This summer's winter weather pattern is likely rooted in a combination of things:

1. Reduced solar output. The sun goes through an 11.1 year cycle with max and min output, discovered by Galileo. It is very rare that the sun gets stuck in between cycles, but that is what has happened. It reached minimum a couple years ago and didn't bounce back as usual. BBC recently reported that the Ulysses space probe has been reporting the sun's output is reduced on every parameter that the probe is capable of measuring. Pretty simple - when the fire dies down, the people next to it start shivering and saying, "Someone throw another log on there..." It recently showed signs of getting the next cycle going again. However, on earth there is usually a lag between max solar energy and max temp in the weather. Daily, the sun peaks at noon, but the high for the day doesn't happen until 2 or 3 pm. Seasonally, the sun peaks in June, but the peak of summer isn't until mid-July. The sun is at its lowest point in the sky in December, but we don't reach the coldest part of winter until 4-6 weeks later.

2. Pacific Ocean in cold phase. The oceans each have a warm and cold phase. The Pacific just kicked into its cold phase (good for many years to come) in 2007.

3. A handful of volcanoes have managed to blast some heat-reflecting particles into the upper atmosphere. Volcanic cooling is a normal occurence on Earth, and we haven't seen much of it in our lifetimes. Mt. Pinatubo in the Phillippines blew up in the early 90s and noticably chilled off the earth for 2-4 years. That's about all we've seen recently. There have been blasts, but none reaching the stratosphere with enough stuff to block out solar heat. In the last year or so, we've had a few small blasts like that. None was really newsworthy, but collectively they've put enough stuff in the stratosphere to create some really nice sunsets around the northern hemisphere. SpaceWeather.com wrote about that recently. A few days later, I was at Fenway Park, watching my first sunset in weeks (it's been THAT cloudy around here this summer, if you haven't been here to see it.) The sunset I saw was just like the one shown on SpaceWeather, which was just like the "Pinatubo Sunsets" I remembered from the early 90s.