WX-MAN's Musings

As of 11am EDT, hurricane Irene was a category 2 storm with sustain winds of 105 mph and gust of 125 mph. Just because Irene is weaker doesn’t mean if you live along the east coast you shouldn’t take this storm seriously. From the National Hurricane Center 11am EDT forecast discussion:

IRENE IS EXPECTED TO REMAIN A LARGE AND DANGEROUS TROPICAL CYCLONE AND HAS THE POTENTIAL TO PRODUCE DAMAGING WINDS…STORM SURGE FLOODING…AND EXTREMELY HEAVY RAINS ALMOST ANYWHERE FROM EASTERN NORTH CAROLINA NORTHWARD THROUGH NEW ENGLAND.

Just because Irene doesn’t have the same kind of strength it did earlier in the week, and is not likely to strengthen much more before it gets to North Carolina. (Note: It still has to cross the Gulf Stream so intensification can’t be ruled out and if Irene does strengthen no one should be surprised despite current forecast trend) Here is Dr. Jeff Masteres from Wunderground.com thought on Irene’s forecast with regard to storm surge:

With its eyewall collapsed and just 24 more hours over water before landfall, it is unlikely Irene will have time to build a new eyewall and intensify. The storm is too large to weaken quickly, and the best forecast is that Irene will be a Category 2 hurricane at landfall in North Carolina on Saturday, and a rapidly weakening Category 1 hurricane at its second landfall in New England on Sunday. However, since Irene is such a huge storm–tropical storm force winds extend out up to 290 miles from the center–it has set a massive amount of the ocean’s surface in motion, which will cause a much larger storm surge than the winds would suggest. At 9:30am EDT this morning, a wind analysis from NOAA/HRD (Figure 1) indicated that the potential storm surge damage from Irene rated a 5.1 on a scale of 0 to 6. This is equivalent to the storm surge a typical Category 4 hurricane would have. While this damage potential should gradually decline as Irene moves northwards and weakens, we can still expect a storm surge one full Saffir-Simpson Category higher than Irene’s winds. Since tides are at their highest levels of the month this weekend due to the new moon, storm surge flooding will be at a maximum during the high tidal cycles that will occur at 8 pm Saturday night and 8 am Sunday morning. At those times, Irene is expected to be near the NC/VA border, then close to Long Island, NY, respectively. Thus, storm surge damage rivaling that experienced during Hurricane Isabel in 2003 is likely in northern NC, southern Maryland, and up Chesapeake Bay on Saturday night. It looks like Irene will pass New Jersey during low tide, which may limit the storm surge inundation to 3 – 6 feet there. Coastal New England from New York City to Massachusetts may also see storm surges characteristic of a Category 1 hurricane during Sunday morning’s high tide, even if Irene has weakened to a tropical storm. I continue to give a 20% chance that a storm surge high enough to over-top the Manhattan flood walls and swamp the New York City subway system will occur on Sunday.

Dr. Masters also goes on to point out that the wind damage from Irene should “be similar to that wrought by some of the strongest Nor’easters of the past 20 years, from Virginia northwards to New York City.” it appears that most of the hurricane force winds with Irene are on the right (eastern) side of the storm and by the time Irene makes it to Virgina, Maryland and Delaware there will no hurricane force winds on the left side (western) of Irene. Power outages and tree damage look to be the biggest threat from winds with Irene with some structural damage to building that you would see in the strongest Nor’easters.

Another major threat with Irene appears to be fresh water flash flooding. Irene is expected to bring rains in excess of 8″ to a 100-mile-wide swath from Eastern North Carolina northwards along the coast, through New York City. Places like southeastern Pennsylvania, Northern New Jersey and southeastern New York have the biggest threat of flash flood and river flooding due to record amounts of rain they have experienced this August. This has already been the 6th wettest August on record for New Jersey.

Tornadoes can’t be ruled out with Irene, even Bob back in 1991, the last hurricane to affect New England spawned six tornadoes ranging from F0 to F1.

For more updates follow me on Twitter – @BrianNeudorff and also subscribe to my weather twitter list of various meteorologist and weather sources.

HURRICANE IRENE RESOURCES:
Wunderground Blog by Dr. Jeff Masters (I read his blog a lot during Hurricane Season) | National Hurricane Center Track & Information on Irene | Skeetobite Weather | Charleston, SC Meteorologist WXBrad | AccuWeather Meteorologist Jesse Ferrell | Hurricane Spaghetti Models | Weather Nerd | Meteorological Musings | Irene Satellite | Eric Berger SciGuy Blog |

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For some reason when the calendar officially says spring the idea of winter weather, especially snow, becomes foreign to us. Our minds quickly can’t fathom the idea that it could actually snow It’s moments like this where our knowledge and memory of weather becomes more selective. I have been a meteorologist for 10 years and it never fails either on the day spring arrives or shortly there after there always seems to be a winter storm.

The ugly truth is that this kind of weather (just like we see in late November and early December before winter arrives) is perfect for developing storms that produce snow, and for some, severe weather. You have a clash of season. With more sunlight and solar radiation the temperatures to the south begin to increase and it wants to spread northward. After months of darkness to the north there’s still plenty of cold and these two air masses begin to clash.

Where these two air masses come together is where you find the path of storms and all the ingredients for major storm systems to develop. That is the case with a storm system moving through and out of the Plains and headed through the Great Lakes into New England.

A swath of moderate snow will spread from North Dakota, through Minnesota, Wisconsin into Michigan, across the Great Lakes and into Western and Central New York before ending in southern parts of New England. This will be a mess for many trying to go about their day on Wednesday. For those who get the snow during the day, with the higher sun angle and increased solar radiation, most roads should remain slightly snow covered to just wet because of the energy making its way to the surface. It’s at night as colder air arrived behind this system when slick roads and icy patches could become a problem.

Here in western New York a general 3 to 6 inches is likely for most. At times this snow could be a heavy wet snow but as temperatures fall and hang in the mid to upper 20s that could make the consistency of the snow a little less wet and a little more fluffy.

The heaviest snow will fall in the higher elevations through southern Wyoming and Livingston counties. Here 4 to 8 inches of snow are possible. As you go farther south near the NY/PA border there will be a mix of snow, sleet and possible rain. That will diminish amounts but still cause some problems. Many of these places are either under a winter weather advisory or winter storm warning.

At least through the end of March, it looks like a good part of the Upper Midwest, Great Lakes and parts of the Northeast could be seeing more winter-like weather than typical spring. Polar jet from the north will not let go and continue to provide fresh colder than average air. This will also make for a stormy pattern.

The storm we are seeing Tuesday night into Wednesday is only one of many that is expected to impact the Great Lakes, Mid Atlantic and the Northeast. It looks like there could be another system in the works for this weekend. Stay tuned.

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Here are a few photos I got tonight of the “Super Moon” at Perigee. It was very bright and watched it rise for about an hour. It was crystal clear in western New York. I have a few more uploaded to Flickr.

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Did you know tonight we are expecting to see something “super”? Yes a “Super moon.” But what makes this moon so “super”?

Tonight, March 19th, will be a full moon, and not all full moons are the same. Full Moons vary in size and brightness due to the oval shape of the Moon’s orbit. It is an ellipse with one side about 31,000 miles closer to Earth than at its farthest point. When the moon is at its closest point we call this Perigee and when it is at its farthest point it is referred to as apogee. Diagram Here.

What makes tonight’s full moon so special is that it will occur less than one hour away from perigee–a near-perfect coincidence. The moon will be just over 211,000 miles away and this perigee moon will be the closest in some 20 years. That is why many astronomers are calling this moon a “Super Perigee” moon.

The good news for a large part of the northeast is that the skies will be clear, especially here in Rochester and western New York. If you want to get the “full effect” the “super moon” it is best to see this as the moon rises in the east at 7:45 PM EDT. This is when the “moon illusion” will add extra effect to the viewing. The “Moon illusion” is not fully understood by astronomers or psychologists, but low-hanging moons look unnaturally large when they beam through trees, buildings and other foreground objects. The next “Super Perigee” won’t occur until the year 2029.

Now there have been rumor circulating around the internet and even posts from some saying the “Super Perigee Moon” is what triggered the Japan quake and tsunami and that is not the case. The gravitational affect will be very small and will only have a slight impact on tides, called Perigee Tides.

Perigee tides are nothing to worry about, according to NOAA. In most places, lunar gravity at perigee pulls tide waters only an inch or so higher than usual. The last “practically super moon” occurred in December of 2008 and nothing happened then.

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(Energy map associated with the 8.9 quake in the Pacific)

I know like me many of you have been clued to the coverage of this magnitude 8.9 quake that shook northern Japan and then caused a devastating tsunami.

A tsunami forms when a strong earthquake like we saw in Japan and rubs against plates. The plates in this part of the world (unlike California, where the slide against each other) go over and under each other. When pressure finally break you get the crust violently displacing upwards and this causes the massive wave.

The tsunami was worst in Japan cause it was getting the full force of the displaced water. As the wave moves away it does get smaller but we are still talking about the potential of a 3 to 6 feet rise in water up and down the west coast and Alaska.

As I write this it is 7:30am PST (10:30am EST) places like Oregon and Washington will soon start to experience the water rise.

Keep in mind when you hear “wave” it is not like the waves we typically see along the shore of the Great Lakes or even the ocean on any given day. These are waves or almost a surge of water. It appears these tsunami waves are coming in waves, where there will be rises and falls and rises and fall an oscillation as the ripple finally makes it to shore.

Along the west coast I wouldn’t expect damage to be high like they saw in Japan but no one really knows what a wave like this can do.

I have already seen comments about solar flares and the moon. I am not versed enough on answering those on my own so before I can comment I will have to do some research and would welcome any links to sites that explain what you are seeing. We will keep you updated and if you have any questions we will do our best to answer them. This is more of a geological event than weather but if we don’t know we will find the answers.

BBC Japan Quake News, Photos & Videos

BBC Wave Map

BBC Why Was the Wave So Big?

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