Thursday, April 26, 2018

Hawaii Flood Disaster Might Have Set New U.S. Rain Record

A destroyed house floats down a Hawaii creek during epic
flash floods earlier this month. Photo via Twitter
@TheRobertHayes
This was little noticed in the media, and I didn't cover it, but there was a terrible flash flood on the island of Kauai about a week and a half ago.

This storm is now reported to perhaps have broken the United States record for the most rain within 24 hours.

The National Weather Service office in Honolulu, Hawaii says a remote rain gauge in Waipa, near the north shore of Kauai recorded an incredible 49.69 inches of rain within 24 hours on April 15. That would break the United States 24 hour record, which has been 43 inches in Alvin, Texas on July 25-26, 1979.

Some of you might have thought the epic rains of Hurricane Harvey in Texas last August beat these records as there were media reports of 50 inches of rain in that disaster.

I checked, and that 50 inches was a storm total from Harvey, not rainfall in just 24 hours. Some places in Texas got 30 inches of rain within 24 hours, which is incredible and extreme, yes, but not the record.

The new Hawaii record is preliminary, not official. There's an outfit called the National Climatic Extremes Committee that will convene, review the data, and determine its validity. If this committee decides everything checks out, then this will become the new 24 hour United States rainfall record.

No word yet on when the committee will come up with a decision.

Whether or not that 49 plus inches of rain is real, there's no doubt the flash flooding on Kauai was extreme.

Military troops and helicopters airlifted at least 220 people stranded by flooding and massive landslides. Many tourists were also stranded. Dozens of homes were destroyed, and many others were demaged.

One woman said she was forced to climb to the roof of her house, and was eventually rescued by someone on a Jet Ski. 

Tourism, certainly a lifeblood of the region, is taking a big hit. The northern shore of Kauai is a mess, but the southern half of the island is fine, and open for business. And so is the rest of the Hawaii island chain.

Some of the moisture associated with the Kauai disaster was picked up and turned into an "atmospheric river" or "pineapple express" that deluged the Pacific Northwest a few days after the Hawaii disaster, notes the Cliff Mass Weather And Climate Blog. 

The atmospheric river produced some relatively minor flooding in Washington State, but nothing like what was experienced on Kauai.

VERMONT, NORTHEAST WATER

In case you haven't noticed, it's wet out there this morning. At least it's not snowing. Just note that there is some high water and minor flooding around.  This water has nothing to do with the above mentioned Kauai flood disaster. However, you should stay away from any local floods and not drive through inundated streets.

Widespread flooding is not expected around here with this rain. Even with snow melting off the mountains, there's just not enough precipitation to cause any serious, widespread floods.

That said, the Ausable River in the Andirondacks was under a flood warning, but that has since been canceled. I wouldn't be surprised if some Vermont rivers approach  minor flood stage today.  Still, current forecasts indicate no real flooding from Vermont rivers today, which is good.

Further north and east, flood watches are up for most of Maine.

It has been a relatively wet April in Vermont. As of midnight last night, the month was running an inch ahead of normal for precipitation this month. It kept raining this morning, showers will continue much of today, and additional showers will come in Friday afternoon or night.

Wednesday, April 25, 2018

Sudden Spring: Generally Warm Outlook For Beginning Of May

Judging from this photo taken at 11 a.m. in  my St. Albans, Vermont
yard, I'm about to have daffodils any second now. 
Well, we finally made it to spring yesterday. Burlington's high temperature was 73 degrees, the first 70 degree reading of the year.

It was the warmest day in exactly six months, as October 24 was the last time it was warmer than yesterday.  

Burlington came close to 70  in February with a record-smashing 69 degrees, and other weather stations in Vermont did pass 70 degrees in February, but as we know all too well, that wasn't really spring.

This, right now,  is really spring. My lawn in two days went from brown to could use a mowing in spots. Trees are budding. My many daffodils, which spent the last month struggling against winter cold and snow, are finally growing like gangbusters and are just about to burst into brilliant yellows and other colors.

Finally!

The outlook for the next 10 days or more is generally very springlike, too!  Temperatures will be near normal today through Saturday -- highs in the 50s and low 60s which is warm enough to keep the plants growing and happy. We will be dodging occasional rain and showers through that period. That's OK. You know what they say about April showers. And for once these aren't snow showers

We get into a brief cool down later Saturday, through Sunday into Monday. Temperatures on Sunday will be especially chilly with highs in the 40s to around 50 with a brisk north wind. That's cool for this time of year, but nothing extreme.

It'll start to warm up on Monday, and at this point most of next week looks quite warm. Of course forecasts could change, but it looks like Vermont will be in the 70s most days next Tuesday through perhaps Friday. We could even see some summerlike 80 degree readings. Definitely not out of the question.

So if you think things are greening up now, just wait until the end of next week!

Inevitably,  there's always a complication. Around May 7 or 8 or so, it looks like at least a brief flip toward cold weather, though of course I don't trust forcasts that far into the future much at all.

I especially hope the American computer forecasting model is wrong - it usually is this far out. But for what it's worth, it forecasts a day or two of pretty much winter cold with maybe a bit of snow and temperatures far below freezing.

That would wreck our welcome emergence into spring by pretty much killing everything that will be growing out there. For now, I wouldn't worry too much about that as that cold prediction is almost surely overblown

For now, enjoy the way everything is greening up!

Tuesday, April 24, 2018

Videos Show Why Waterspouts Aren't Always So Harmless

This house in Fort Walton Beach, Florida was trashed by Sunday's tornado.
Waterspouts - basically tornadoes over water, are usually pretty harmless. They're usually not that strong, and more often than not dissipate before coming on shore or just afterwards. The normally cause just minor damage.

A large proportion of waterspouts are regarded as "fair weather waterspouts" because they form beneath garden variety showers and thunderstorms.

You gotta watch these things, though, because sometimes there's more than just a minor waterspout going on.  You should avoid them at all costs because some waterspouts are actually full-fledged, dangerous tornadoes associated with violent thunderstorms.

This more menacing type of waterspout is no different - and just as dangerous - as a full-fledged land tornado.  They just happen to form over water. That happened Sunday in Fort Walton Beach, on the Florida panhandle coast. A waterspout formed in the Gulf of Mexico and came onshore.

The waterspout came ashore as an EF-1 tornado, with winds of between 86 and 110 mph. That's certainly not the strongest tornado possible, but that kind of twister is certainly capable of causing damage, as it did in Fort Walton Beach.

When a tornado hits a populated area, you're sure to get lots of video, and some striking ones came out of Fort Walton Beach.

Several homes and other buildings were damaged by this twister, one of about five that hit Alabama and Florida Sunday. Luckily there were no serious injuries.

 Here's a balcony view of the twister passing close by as it came ashore.



Here's another, close view of the tornado:


There's surveillance video of Fort Walton Beach City Hall. Damage looks minor, but even a relatively weak one like this can be scary. Note in one clip how the twister moves a pickup truck:

Monday, April 23, 2018

Gorgeous Sunday Was A Classic Vermont April Day For Variety Of Cool Reasons

If you look closely, you can see plants beginning to emerge
in my perennial bed in the foreground amid warm sunshine
Sunday in St. Albans, Vermont 
I really hoped you enjoyed Sunday if you were in Vermont.

It was wall-to-wall sunshine. Most valley locations were in the 50s. Warm enough to enjoy, cool enough to get some outdoor work done effiiciently.

Today will be awesome, too, albeit warmer. Most of us will get over 60 degrees.

By many standards, Sunday was a classic Vermont April day. This is the time of year when you're most likely to get a cloudless sky, very low humidities, a cool breeze but warm sunshine.

Though I would note that April is fickle, as we've really been reminded about this year. We're still recovering from a long string of days with snow and cold rain. And we have another stretch of chilly rains to deal with. Though later in the week, the snow will be confined to the mountains, if it snows at all.

Dewpoints were remarkably low on Sunday in Vermont - mostly in the mid-teens. Essentially that meant temperatures would have had to drop into the mid-teens to create frost, or freezing fog around this neck of the woods. There was definitely no freezing fog to be had in Vermont on Sunday.

I'm sure nobody was complaining  about that fact.

Low dew points mean low relative humidities. Relative humidity represents the amount of water vapor in the air. It's the percentage of the maximum amount that the air could hold at a given temperature.

Basically that means the air on Sunday was nowhere near as wet as it potentially could have been

April is the season in Vermont where you do get quite a number of days like Sunday -- clear and super dry.

One big reason it can get so dry on certain days during a Vermont April is because there are no leaves on the trees yet.  Leaves emit a lot of water. Vermont is mostly forested. A very large oak tree can transpire 40,000 gallons of water per year. Imagine how much water vapor all those Vermont trees release into the atmosphere each summer. The air would have to be wetter than it is this time of year.

The dry air means daily temperatures swings are big between dawn and the afternoon. More humid air can hold heat longer, so after the sun sets, it doesn't cool off all that much after the sun sets.

Dry air, like we had yesterday and am having today means as the sun sets, it's easy for heat to radiate to outer space rather than hang around where we are. You might have noticed as the sun began to set last evening, it got very chilly very fast.

Yesterday in Burlington, we started out at 28 degrees and ended up with a high of 58 - a pretty big range. Today will have an even bigger temperature range. We started the day right around 32 degrees and the forecast high in Burlington today is 65 degrees.

The occasional very dry April days we get is one reason why we have occasional brush and grass fires this time of year. Last year's weeds and plants are all dead and dry. The arid April air dries them out further and there you go with the blazes.

It's been fairly wet this month, so the fire danger today isn't extreme. But I'd still postpone burning that brush pile until it gets a little wetter -- which will happen later this week.

You'll notice the early spring plant life does love these sunny, mild afternoons. The grass is noticeably greener than it was Friday, and I bet your early sprouts like daffodils and hyacinth are much taller than they were a couple days ago.

All bright and sunny weather must come to an end. Wednesday and Thursday definitely are looking rainy at this point.

Sunday, April 22, 2018

Oklahoma Wildfires Are Becoming An Ugly Pattern

A wildfire explodes viciously as it encounters parched eastern redcedar durimg
devastating Oklahoma wildfires this past week.
Photo by Alan Broerse. 
Oklahoma never used to be famous for earthquakes and wildfires.

That's California's job.

People associate Oklahoma with tornadoes, and they still happen there very frequently. (That said there has so far been a real dearth of Oklahoma tornadoes this year.)

But earthquakes, and now wildfires are very Oklahoman, and it's pretty easy to blame the fossil fuel industry, which is such a large part of the Oklahoma economy. Especially the earthquakes, though the wildfires might just be tangentally related to the fossil fuel industry.

Oklahoma is now the most earthquake prone state in the United States. Most of them are caused by wastewater disposal. Oil is extracted from the ground, but a lot of is mixed with briny water. The water needs to be disposed of, so it's injected well below the earth's surface, below the aquafers so drinking water won't be contaminated. This causes earthquakes.

But this is a weather and climate blog, and we're really here to talk about wildfires. This is the third year in a row Oklahoma has had devastating wildfires, and this year appears to be the worst.

At least two people have died in the wildfires over the past week or so and dozens of homes have been destroyed.  One fire in Oklahoma had burned 440 square miles and was only 15 percent contained as of Thursday morning.

There was at least some temporary relief Friday and Friday night for Oklahoma: Numerous showers and thunderstorms dumped some fairly decent rains on the worst of the fire zone. And some more showers are in the forecast this week. But the damage is really done. And extreme.

So what's the deal with all these Oklahoma wildfires over the past three years?

Bob Henson in his Category 6 blog has a great overview of what's been happening.

In the late winter and early spring, strong, dry winds often blow in from the west. The winds warm up and often become hot once they get down the slopes of the eastern Rockies, so it's basically a blowtorch by the time you get to Oklahoma.

Relative humidities can often drop into the single digits during these episodes and winds can gust to between 40 and 60 mph, or even more in some instances.

These hot, dry early spring winds aren't new to Oklahoma, and they have always spawned wildfires.

In recent years, though, droughts have gotten extraordinarily bad, particularly in western Oklahoma and northwestern Texas.

Mixed in with these droughts have been extraordinarily wet periods, which encourages vegetation to grow vigorously. For instance, 2015 was a record wet year, and it was warm. Things grew well into the late fall, so there's lots of extra grasses, shrubs and whatnot out there.

Then there was a flash drought in early 2016, and a lot of that extra vegetation went up in flames. This boom/bust cycle of heavy rain and drought has continued. This feast and famine regime could be related to climate change, so there's your fossil fuel link to this wildfire story.

Then there's shrubby tree called the eastern redcedar. It's a tree-sized juniper that you commonly see in the Plains. (I see a lot of them when I visit my in-laws in South Dakota, for instance.)

Before Europeans came into the picture a zillion years ago, lightning or fires set by Native Americans meant the eastern redcedars only lived in small canyons, ravines and outcroppings.

Now, eastern redcedars are spreading super fast across the Oklahoma landscape. Cedar smells great, doesn't it? But the oils that cause that nice aroma turn the trees into firebombs when it gets dry. Basically throw flammable oil on a discarded Christmas tree and thats what you get when eastern redcedars get hit by wildfires.

Instead of low flames skittering across open grasslands, you get the wildfires hitting groves of these trees, creating hot, big, explosive flames that are extremely dangerous, and more likely to set nearby homes and other structures on fire.

Bottom line: The past three years might be a fluke in Oklahoma wildfire history. But the real fear is that this could be a tragic, dangerous new normal for the Sooner State.

Saturday, April 21, 2018

Mount Mansfield Reaches 100 Inches Of Snow; Meltdown About To Start

My snowy commute to work Friday morning. I'm really hoping I don't have
to experience this again until November at the earliest. 
UPDATE:

Some interesting snow data and dangers from Mount Washington, New Hampshire have come to light.

There's an avalanche warning up there today, including in the ever-popular Tuckerman's Ravine. A bunch of snow over the past few days falling on deep, previous layers has created a high risk of human-induced and naturally caused avalanches

So if you were going to go to Tuckerman's on this nice weekend for backcountry skiing, don't bother. Too dangerous.

By the way, I imagine there's a risk of avalanches to back country skiers atop Mount Mansfield, Vermont, too.

Meteorologist Tim Kelley, of NBC10 and NECN fame in Massachusetts (he's also a noted ski and surf forecaster) noted some interesting stats from the summit of Mount Washington.
Today was the 21st day in a row in which at least a trace of snow fell on Mount Washington. They've had a foot of snow in the past week and 52 inches so far this month.

PREVIOUS DISCUSSION:

All but five of Vermont's ski resorts are closed for the season, but certainly not for a lack of snow, which is usually the case this time of year.  

It's just that few people are in the mood to ski this time of year, being late April and all.

The high elevations of Vermont, New York and New Hampshire are still deep in snow after this snowy March and April. 

A meltdown is finally going to start over the next few days, and I would assume it will continue almost uninterrupted until it's all gone. 

The summit of Mount Mansfield had 100 inches of snow on the ground as of yesterday, the most this winter, and an unusually high amount for late April. 

If you want some great late season skiing, go for it. Jay Peak is going to stay open into early May. Why not? They've had 11 inches of snow in the past week and 378 inches (31.5 feet!) for the season.

Killington always is the first or among the first to open for the season and is the last to close in the spring or close to it. They expect to stay open into May as well. 

Even some populated areas of Vermont still have plenty of snow on the ground. The high elevation town of Sheffield in the Northeast Kingdom had a snow depth of 18 inches as of yesterday.  Granby had a snow depth of 15 inches. 

Still some snow in my yard Friday evening in St. Albans,  Vermont
making spring gardening a challenge. Remaining snow do disappear today
As I've been saying for the last few days, we in the valleys looked to be finally pretty much done with snow. 

I had to tiptoe around remaining areas of snow in my yard last evening to get some garden work done. But that snow will be completely gone by later today. 

It won't be particularly warm today and Sunday (40s and low 50s) for highs, but sunshine both days will feel great after all the clouds we endured. 

St. Albans, Vermont today will break its seven consecutive day streak of days with snow or freezing rain. Burlington will end its nine consecutive day streak of measureable precipitation.  

With the warming temperatures on the way, either spring skiing or spring gardening look like great options, especially Monday and Tuesday under sunshine and valley high temperatures near 60 degrees. (At the moment,  Burlington, Vermont's forecast high on Tuesday is 66 degrees. Ahhhh.)

Also, there's no change to the forecast for the type of precipitation we'll get with the next storm system, which will be here mostly on Wednesday and Thursday. Expect rain, not snow.

Which will be an enjoyable change of pace, huh?

Friday, April 20, 2018

Most Of This Snow Wasn't Even Caused By An Organized Storm

Once again, my yard in St. Albans, Vermont was a winter wonderland this
morning. About 1.3 inches new when photo taken, still snowing (7:00 a.m.)
Usually when it rains or snows, it's associated with a low pressure system passing nearby.

One such storm scooted by New England yesterday morning, but the main driver of the lousy,  unseasonable snow we're having is what is for this time of year an amazingly large and deep pool of cold air high above us. 

That cold air up there is extensive (though it's now beginning to wane)

At very roughly 5,000 feet above the Earth's surface, it was below freezing from Minnesota through New England and on into eastern Canada. That cold area extended all the way down into northern Alabama.

No wonder there were wide areas of frost and freeze warnings and advisories in the Ohio Valley and Mid-Atlantic states early this morning.  And no wonder it was a frigid 18 degrees atop Whiteface Mountain, New York at one point yesterday.

This upper level cold air is a symptom of a storm in the upper levels of the atmosphere, and sure enough, there was one pretty much centered in New England Thursday.  Usually storms at the surface are centered to the east or southeast of the upper low and that was the case yesterday. (It was near Nova Scotia early this morning.

The sun angle this time of year is high, so when the sun filters through the clouds when it's that cold aloft, pockets of warmish air rise, form clouds and showers. Yesterday, here in Vermont, those were mainly in the form of snow showers.

It was cold enough aloft to chill the snowflakes that some of them made it to the ground in the Champlain Valley Thursday afternoon while temperatures were in the low 40s. By late afternoon, some of the snow showers were briefly heavy-ish and began to accuumulate.

Overnight, the snow in Vermont came down in earnest. Of couse, unlike during the day, the snow had no help from the sun causing rising pockets of air.

Instead moisture pinwheeling from offshore Canada around the surface storm up there and the upper level low high above brought wet air down from Canada on to us. The moisture would rise up the western slopes of the Green Mountains, where it was wrung out as snow.

My place in St. Albans is where land begins to rise in elevation east of Lake Champlain. as of 6 a.m. I'd received about an inch of snow, and it was stil coming down at a good clip.  I'm sure we'll get reports of several inches or a half a foot or even more closer to the Green Mountain summits.

At roughly 5,000 feet above sea level, it was below freezing yesterday in
the blue area inside the black line 
The good news for spring snow haters is the moisture flow and the cold air aloft are going to gradually wane.

The snow today will keep getting spottier and spottier and more confined to the mountains. A few raindrops will come down in the valleys.

The upper levels of the atmosphere are still cold today, so we won't be able to warm up too much today. The April sun, though strong, can only do so much when it's that cold aloft, and when there's clouds around.

But the atmosphere will warm, and day by day, you'll see improvements. As noted in previous posts, Saturday will also be chilly, but at least there will be some sun. Sunday will be cool for this time of year,  but not bad. Temperatures near 50 will be easy to take after all the cold and snow over the past week or more

We're still looking at 50s and 60s Monday and Tuesday.  The next storm arrives late next week. We're still not sure how big or small this next one will be, but it surely looks like it will be too warm for snow with that one.

For those who like heat, here's a ray of hope for you. Admittedly, long range forecasts looking out several weeks or months are not known for their pinpoint accuracy, but a long range prediction by the National Weather Service issued yesterday calls for generally warmer than normal temperatures in the Northeast during May, June and July.

On the other hand, European models suggest we might have a cool May.

We'll see