Category Archives: Cool Images

Epic Lake Effect Storm

As you know, I try to stick to local weather, but from time to time, a weather event occurs that you just can’t help talking about. Over the course of the last two days, areas in the snow belts around the Great Lakes have been pummeled by an epic lake effect snow event. The snow belt in the Tug Hill Plateau south of Buffalo has seen the worst of it, with snowfall totals in certain neighborhoods already approaching six feet. And it isn’t over yet!

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From Wil Fuentes on Instagram (@wilfuen) – sourced from Time.com

Based on observations from the National Weather Service data, it looks like wide swathes of the area south of Buffalo just got hammered with snowfall ranging anywhere from 36″-60″ (3-5 feet!) of snow.

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Measurements of snowfall around Buffalo – check out that 57″ number south of Elma, NY
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National Snow Analysis from National Weather Service – 35″+ observed in a period of 24 hours!

The snow is so brutal that the Buffalo Bills are scrambling to clear Ralph Wilson Stadium ahead of a scheduled game on Sunday. Lake Effect Snow Warnings are still in force in the area – and there are forecasts of an additional two feet of snow in the next couple days. The NFL may need to move or postpone the game if the Bills can’t get the snow cleared in time. The team is giving away tickets and such to anyone who’ll help dig out.

What is Lake Effect Snow?

Lake effect snow occurs when very cold air flows over a relatively warm body of water. As the cold air blows across the surface of this warmer body of water, it can quickly become saturated with moisture that evaporates (cold air can become saturated quickly because it inherently cannot hold that much water vapor). When this now saturated airmass hits the opposing shoreline, orographic (terrain) forcing causes the air to rise up (leading the airmass to become so cold that the moisture is forced to precipitate out), and provides the energy to spark of often intense, highly localized precipitation events.

This particular event has been so prodigious partially because of the alignment of winds over the surface of Lake Erie. Fetch, or the distance over which air flows across a body of water, greatly influences the severity of a lake effect storm. The longer the fetch, the more time the air has to pick up moisture off the water. In this case, the water temperature of Lake Erie is still relatively warm since air temperatures have not been that cold yet, and the winds are oriented such that the fetch is maximized over the surface of the lake (from west-southwest to east-northeast). Conditions should improve rapidly by Friday as high pressure over the Central Plains moves to the east and winds shift to the northwest.

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Typhoon Neoguri Image


Despite the fact that Typhoon Neoguri shares a name with a well-known brand of packaged ramen, it certainly is no joking matter, as you can see from the impressive satellite image captured recently. Although the storm has weakened from a Category 4 Super Typhoon, it is still a powerful Category 3 storm currently churning up the East China Sea.

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This storm is bad news for Japan, especially the large populations living on the southernmost home island of Kyushu. Forecasters believe Neoguri will continue to weaken rapidly under the influence of increasing wind shear, but it is still set to make landfall on Kyushu some time Thursday as a Category 1 storm. The mountainous terrain of Kyushu will likely provide orographic enhancement for the rain bands coming off of Neoguri (the upslope side of the mountains facing Neoguri’s onslaught will have the tendency of squeezing out precipitation from the rain bands).

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Weekend Weather, Hurricane Arthur Update – Jul 4, 2014 @ 10AM EDT

As of 9AM EDT, Hurricane Arthur has weakened somewhat from its peak intensity as a Category 2, and sustained winds have declined to 90mph. However, its eye is still clearly visible, and as you can see below, the storm is maintaining a symmetrical appearance with good outflow in all quadrants, meaning this is still quite a powerful storm. As Arthur continues moving northeast, it is expected to weaken rapidly upon entering much cooler waters and with increasing vertical shear from the codl front seen below.
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Track Forecast

Forecast models are in very close agreement about Arthur’s track over the next 12 hours or so. As you see below, they are tightly clustered around the 40N, 70W benchmark. Hence, forecast reasoning has not changed much since yesterday night. Arthur is expected to continue its northeast track and speed up under the influence of the cold front depicted above, moving offshore of New England and into the Canadian Maritimes as it makes extratropical transition.

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What This Means for Us

As expected, Arthur will be bringing multiple rounds of rain to the entire Northeast over the course of the day today. You can already see Arthur’s outer rain bands on our regional radar (you’d see it in the standard 124 nautical mile radar, but I’ve inserted an image of 248 nautical mile range radar image to see the storm better). As Arthur accelerates and makes its closest pass to this part of the country, we’ll see repeated bands of rain moving on shore. You can expect periods of heavy rain and thunderstorms, interspersed with some dry spells under cloudy skies.

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The Rest of the Weekend

Once Arthur and the cold front clear the Northeast, we will see a return to a spectacular weekend with high pressure building back in. Sunny skies, mild, and dry conditions will prevail across the entire region with high temperatures in the low-mid 80s on both Saturday and Sunday. As the high pressure moves to our southeast, we’ll see a return flow from the backside of the high pressure ushering in another warm, humid airmass for the beginning of next week.

 

NYC Afternoon Weather Update – Severe Tstorms in Vicinty – Jul 2, 2014

You may have already experienced it, but if you haven’t you’re probably seeing some huge clouds forming on the horizon. We’re in for some stormy weather this evening, as the Storm Prediction Center and our local forecast office have us under a Severe Thunderstorm Watch. The hot, humid atmosphere, along with ample sunshine earlier today, has made the atmosphere moderately unstable, with CAPE values in the 2000-3000 J/Kg. This, along with mid-upper unidirectional shear will supply ample energy for strong to severe storms, with the greatest threat being frequent cloud to ground lightning and damaging winds.

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As you see above, there are already strong storms in our vicinity. The storms north of the city have met severe thunderstorm criteria (wind gusts in excess of 58mph, hail greater than 1/4″ in diameter, or a tornado). More storms are forming to our southwest, so NYC itself should not be immune to the threat later on. Check out this image of a classic towering cumulonimbus (thundercloud) below!

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Really Cool Image – Von Karman Vortex Street

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When air flows are blocked by obstructions, such as buildings, trees, mountain ranges, or in this case, a mountainous island, all sorts of interesting effects can occur. Just as flowing water hitting a rock will form swirling eddies, flowing air has the same tendency, which you can plainly see int he image above. We’re usually not able to see these effects so vividly, though you’ll often feel them in the form of turbulence.

From the Facebook page of the National Weather Service Weather Prediction Center:

One of the lead forecasters at WPC was taking a look at the visible satellite imagery in the Pacific near the Baja California Peninsula and noticed some swirly action. If you take a look, there’s several swirls being caused by a volcanic island called Isla de Guadalupe. There’s also one right next to the coastline. How many can you count!?

We have satellite and radar imagery on our webpage alongside the surface analysis–if you want to take a look, visit our website (www.wpc.ncep.noaa.gov) and take a look under the current weather!

NYC Nowcast – Apr 8, 2014 @

Quick update here: skies will gradually begin to clear as clouds associated with the rain storm last night move offshore. As you can see from the satellite image below, sunny skies are already entering portions of Northern NJ. Depending on the time we get under clear conditions, we could very well see high temps hit 70 except in Long Island and coastal CT, where an onshore southwest wind will keep things cooler.

Also of interest, check out the wave clouds out over Central PA! Just as objects in the path of a water can cause eddies and waves to form behind them, you can get the same effect with air flowing over mountain ranges. You can’t surf these (maybe with a glider?)
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Cool gif – Severe Thunderstorms in the Plains, Apr 3, 2014

Check out this satellite loop of a line of severe thunderstorms over eastern Oklahoma extending northeast into western Missouri. You can see the classic telltale signs of explosive thunderstorm growth here. Notice how at the outset, the line of clouds near the center of the frame are relatively thin, but then balloon out as time goes by. What’s happening here is that the cumulonimbus (thunderstorm) clouds along this line are growing so rapidly that they are hitting the top of the troposphere. Since water vapor has a difficult time penetrating into the stratosphere, it gets forced out laterally instead. Indeed, the Storm Prediction Center in Norman, OK has issued a mesoscale discussion, along with severe thunderstorm warnings and tornado watches for much of the area.

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NYC Weather Update – Apr 3, 2014

Get out there and enjoy the sunny, mild weather while if you can today. We caught a nice break and got enough sunshine today that we’ll probably top 60 in quite a few spots around NYC. Clouds will increase over the next couple hours. Conditions will steadily deteriorate as a surface low pressures system currently spawning some severe weather over the Plains states tracks northeast into our area. Screen Shot 2014-04-03 at 1.49.36 PMFriday – keep the umbrella handy as periods of showers are likely to occur throughout the day, with increasing coverage and intensity later on in the day into the overnight hours. An steady onshore breeze will usher in much cooler air off the ocean (sea surface temperatures offshore of the region are only in the upper 30s to low 40s). As a result, high temp will hover in the mid 40s.

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Saturday – the storm system bringing us rain Friday into Saturday will advance a warm front through the area, and we’ll see a rebound in temperatures and gradually clearing skies. High temps could again top 60.

Sunday – another pleasant and mild spring day as high pressure moves into the area. Mostly sunny skies with a high again near 60.

Monday – our next shot at rain will come Monday-Tuesday of next week, with a storm system forecast to develop in the Gulf. This storm will track northeast through the Ohio valley into the Great Lakes, and a trailing cold front will bring us some steady rain. High temperatures Monday will be around 60 with warmer air flowing from the southwest ahead of the cold front. Long Island and CT shorelines will see cooler highs with an onshore flow.

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Our next shot at rain – a low pressure system moving from the Gulf into the lower Great Lakes, and a trailing cold front.

Really Cool Graphic – Frozen Great Lakes

It may be spring now, but it certainly doesn’t look or feel that way for the Great Lakes, most of which are still ice-bound. Superior, Huron, and Erie are still almost entirely covered by ice, while Michigan is less than half covered. The only lake not ice-bound this winter has been Ontario at the far-right. Image from LANCE MODIS taken on March 16th.

You may be wondering why Lake Ontario is the exception to the frosty rule here. Ontario’s average depth is about 283 feet, only Superior has a greater average depth (Erie is the shallowest, so even though it’s further south than Ontario, it’s often the first to freeze). Furthermore, Ontario is located at a lower latitude than Superior and Huron, and it’s relatively smaller surface area maximizes its heat retention.

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