A Minnesota Dryline

Almost two months have elapsed since my last post. An entire winter is now nearly behind me, and with meteorological spring having sprung as of yesterday, my eyes turn once again to the coming storm season. MN Dryline 5102011Going through my old radar images, I came upon this one. Click on it to enlarge it, then note the station obs and wind barbs on either side of that fine line west of Minneapolis. That sure looks like a dryline to me, but what's it doing wandering around central Minnesota like a little lost orphan? The Great Lakes are not the land of drylines, but we do get them occasionally, and as out in the Great Plains, they can serve as a forcing mechanism for severe weather. Notably, in the 1965 Palm Sunday Outbreak, what Theodore Fujita called a "dry cold front" featured prominently in his analysis of the synoptic conditions. Although Fujita called the air behind the front "cooler," a look at the station observations reveals that what really characterized the difference on either side of the "front" wasn't a rapid drop in air temperature but in dewpoints, and a change in wind direction, with surface winds veering abruptly from the south to the southwest. The radar grab shows similar conditions on May 10, 2011, with supercells initiating along a line of strong convergence. Where the southernmost cell is just starting to fire, check out the obs on either side of the fine line. The temperature is the same, 90 F degrees, but the dewpoint drop is as much as 13 degrees. That may not be as radical as what you'll find in the Texas panhandle, but in the Great Lakes, it's an eye-opener. There were tornadoes in eastern Minnesota on this day: May 10, 2011, SPC Storm Reports. The location of the three reports on the SPC graphic leads me to think that the cell I mentioned in the previous paragraph may have been the culprit. With dewpoints in the upper 60s to low 70s, it appears to have had plenty of juice to work with. For a dryline to occur in the Great Lakes means that a system is potent enough to wrap in dry air this far east from the desert Southwest. That means that a lot of things have fallen into place to create a potentially tornadic setup, including not only an obvious lifting mechanism but also ample bulk shear and moisture, and southerly or southeasterly surface winds. In other words, here in my backyard, a dryline is a red flag that things are about to pop and a chase day is at hand.

July 6, 2014, Cutlerville Tornado

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Tornado damage southwest of Division and 54th St.

It is a weird feeling when a tornado strikes the neighborhood where you used to live, particularly when you weren't expecting tornadoes at all that day. That's how it was two-and-a-half weeks ago on Sunday, July 6. No one saw it coming--not anyone who lived in the stricken area, not the National Weather Service, not any Michigan-based storm chasers I know of, and certainly not me. All I thought was, "Dang, that's some crazy lightning coming out of that cell to my northwest!" even as an after-dark tornado chugged its way from Byron Center across Cutlerville and Kentwood toward its last gasp near Breton Road south of 28th Street.
Turning onto Andover St. from Eastern Ave.

Turning onto Andover St. from Eastern Ave.

I'm writing about it only now because I've had my hands full with other things. It's no longer news, but it certainly deserves some kind of writeup in this blog. After all, it was the most significant tornado to hit the Grand Rapids area in years, it caught the NWS by surprise, and it missed my old apartment by only a block. (Come to think of it, another tornado in 2006 also missed my present apartment by only a block, but I wasn't around to see it. I was heading home from my previous day's chase in Illinois. Lots of irony there, but I'll leave it alone and stay on topic.) The Storm
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Tree uprooted along Division Ave. south of 54th St.

It was evening, and I was parked by the railroad tracks out near Elmdale, practicing my saxophone--which, if you know me, you understand is a regular habit of mine. The heat and humidity of the day had built to a slow boil beneath a capped atmosphere, but it appeared that the cap was breaking. Through the haze, I could see what looked like mushy towers off to my north. Right around sunset, I saw lightning streak through a cloud bank moving in from the west and thought, Nice. Bring it on. With mid-level winds forecast to be weak, I wasn't expecting more than garden-variety storms, but given this year's largely stormless storm season here in Michigan, any kind of flash and boom would be welcome. With my practice session not feeling particularly inspired, I decided to call it and head home. The storm didn't appear to be moving fast--not surprising, given the weak steering winds--but just north of my path . . . wow, that lightning was ramping up something fierce. I contemplated intercepting the cell, which clearly was quite active, but I had neither my laptop and radar with me nor my camera, nor, frankly, much desire. Sometimes it's nice to just sit at home and let a storm rumble overhead. By the time I arrived in Caledonia, the cell was flickering like a strobe light, and for half a minute, with more lightning advancing from the west, I thought I would sit in the church parking lot on the west end of town and let myself get eaten. Then I thought, Nah. Slow-moving storm with a lot of precipitable water--I just wasn't into getting drenched during the mad dash from my car to my apartment. Besides, something in me really wanted to take a gander at the radar.
Meso Kentwoo

Mesocyclone over Kentwood, Michigan.

Once inside, I fired up GR3. Base reflectivity showed an amorphous clump of cells surrounded by lots of green: pretty much the disorganized, high-precipitation mess I expected. Then, out of pure force of habit, I switched to storm-relative velocity. Hmmm . . . what was that? Weak rotation just west of the airport radar seven miles north of me? That seemed odd. Curious, I back up a scan, which showed that the rotation had been stronger over Kentwood a few minutes earlier (see image.) Time for a look at the VAD wind profile. Well, now: mid-level winds were stronger than I had expected, around 40 knots, with southerly winds veering nearly 90 degrees through the lowest 4,000 feet. That would explain that. Going by reflectivity only, I'd never have suspected, but there it was, a definite mesocylonic signature. What did the previous scan show? Yikes. Really? There over South Division Street, sitting on top of Cutlerville--that was one potent-looking couplet.* Kind of scary, really. Surface-based CAPE was something like 2,000, and forecast low-level helicity was more than adequate, over 200 m2/s2 in the lowest kilometer. Still, reflectivity looked like crap, the storm was wrapped in rain and not even severe-warned, and besides, this was Michigan. And that was two scans ago; the rotation had weakened considerably as it approached the airport. That would be the end of things.
Supercell organizing near Ionia.

Supercell organizing near Ionia.

But it wasn't. As the storms moved east, the low-level jet spiked considerably, and even the 500 mb wind got a brief burst of 50 kt. Over by Ionia, a cell began to organize, and this time there was no mistaking the telltale look of a supercell in the reflectivity product. KGRR issued a severe thunderstorm warning with mention of the possibility of a tornado.
A scan later, storm-relative velocity shows pronounced rotation. Base reflectivity (not shown) also showed a well-defined hook.

A scan later, storm-relative velocity shows pronounced rotation. Base reflectivity (not shown) also showed a well-defined hook.

There were in fact four tornadoes according to the SPC's final tally. The last three off to the east were brief EF0s, but the first one, which had initially caught my attention, did high-end EF1 damage in Cutlerville and injured six people. Damage in My Old Neighborhood
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This used to be a warehouse on the west side of Division Street.

After doing its worst damage on the west side of Division Street, the tornado moved northeast through my old neighborhood, Leisure Acres. The second photo at the top shows the view that greeted me as I turned off of Eastern Avenue onto Andover Street. Halfway down Andover, my old apartment was untouched, but just a block east (and no doubt to the south, though I didn't look) was a trash heap: trees snapped and uprooted, big branches torn off, here and there part of a roof missing--all the signs of a weak tornado. But of course, weak is a relative word; a wind that can do that kind of damage is anything but weak, as those in its path would be quick to point out. Nevertheless, there's a significant difference between a 100 mph wind that does mostly minor structural damage and a 180 mph wind that levels homes completely.
House on Andover St. with its roof and side ripped off.

House on Andover St. with its roof and side ripped off.

Half of the photos in this post were taken in the Leisure Acres neighborhood along my old street, Andover; the rest were taken on the west side of Division south of Fifty-Fourth Street. The damage on Andover was primarily tree damage, though that was obviously significant, and as you can see, homes didn't escape unscathed. The worst appeared to have been the house shown to the right with part of its roof and side ripped out out by the wind. I was told that much worse damage occurred to the west along Clay Avenue, and while I didn't try to enter that area, a brief jaunt down Division Street revealed places where the damage was more intense. The most significant was what appeared to have been a large warehouse building that got completely destroyed--just a pile of blocks and steel beams, as you can see in the photos.
One good egg. He just showed up with his chainsaw, ready to help.

One good egg. He just showed up with his chainsaw, ready to help.

In the aftermath of severe weather events, communities tend to pull together and ordinary heroes emerge from outlying areas, bringing with them such skills as they possess and the desire to make life a little easier for those dealing with the destruction of their property. This man with the chainsaw was wandering along the street from house to house, inquiring whether anyone needed help sawing up downed trees. Giving what he had to offer. I asked his name and wrote it down, and now I've lost it. In the very slim chance that he should happen to read this article: Bravo, sir! Generously played. "We Had No Warning": The NWS's Dilemma Of course the NWS got hammered. "We had no warning," storm victims said--and while most of the time that's untrue, in this case they really had no warning. But before anyone makes the usual foolish comments about the NWS's ineptitude and how they never get anything right--which is simply not the case--it would pay to understand a few things about tornadoes in Michigan. Let's start with this fact: The typical tornado-breeding systems of the kind that produce significant (EF2 and higher) tornadoes get forecast quite effectively here in West Michigan, as elsewhere in the country. Meteorologists are on top of such setups; they watch these systems develop days in advance and are most certainly monitoring each one closely as it arrives, with varying degrees of concern depending on its characteristics.
Nothing left but a pile of cement blocks, wood, and steel.

Nothing left but a pile of cement blocks, wood, and steel.

That leaves the atypical tornado-breeders: systems whose features wouldn't automatically trigger alarm, whose storms may occasionally produce brief, weak tornadoes that spin up with little or no advance notice. Storms like these--often squall lines and sometimes, as in the case of July 6, unremarkable-looking rainy blobs--produce no persistent, telltale circulation in a storm's mid-levels that a radar can detect twenty minutes before a tornado forms. Such storms are difficult to impossible to warn. In the case of a squall line, small circulations can hop around from scan to scan on the radar, now here and now there, and most of them never produce. The rare tornado that does occur can materialize between radar scans, which until very recently have taken four-and-a-half minutes to complete in severe weather mode. A lot can happen in that time, and on July 6, it did. Without going into details that most of my readers are no doubt familiar with, the lads at KGRR deal with proportionately more of these atypical scenarios than forecasters west of the Mississippi. The difference between a Great Plains supercell and the kind of stuff we normally get in Michigan is substantial, and for forecasters here, that means fewer opportunities to look like heroes and plenty more situations in which they're damned if they do and damned if they don't. When they issue a warning and nothing happens--which is frequently the case with squall lines--the public accuses them of crying wolf; when they don't issue a warning and a tornado pops up out of nowhere, the public thinks they're idiots.
Debris festoons a tree and litters a yard on Andover St. a block from my old apartment.

Debris festoons a tree and litters a yard on Andover St. a block from my old apartment.

They are far from idiots. They are experts who deal with factors in the warning process that most people know nothing of. Their job is not an easy one, and anyone who believes he or she could do better is woefully ignorant of the complexities of severe weather and warnings. Think otherwise? Fine. Go ahead and spend a few weeks at the peak of severe storm season, trying to nail that volatile blob of Jell-O called the atmosphere to the wall. It'll be an eye-opening experience as, equipped with state-of-the-art technology, you discover the difference between forecasting and fortune-telling. Ironically, the Cutlerville tornado occurred shortly before KGRR was slated to implement the new SAILS update to their radar software. It's amazing to see how drastically this software reduces scan times in severe mode--I now get level 3 downloads in as little as a minute and always substantially less than the nearly five minutes of pre-SAILS days. Had SAILS been operative on July 6, the tornado might well have been detected in enough time to issue a warning. Or not. Microscale conditions can change so rapidly that some tornadoes will still slip through the cracks. But the odds of detection have just improved significantly. ------------------ * The image shows the meso over Kentwood. I have tried unsuccessfully to render the more vigorous Cutlerville scan on both level 2 and level 3 data from NCDC archives on GR2AE and GR3. After several hours of fiddling with the data files and consulting with chasers who are more technically gifted than I, I've concluded that I need to get some hands-on help figuring out how to use NCDC's archived data. Sorry--I've done my best.

February 20: The “Everything” Storm System

February 20 2014 Davenport I find this screenshot of the Davenport, Iowa, radar fascinating for its variety. Captured at roughly quarter to five in the afternoon eastern time, it shows just about every conceivable kind of Midwestern weather in operation simultaneously. Tornadoes and funnel clouds. Squall line with embedded supercells. High winds. Hail. Flooding. Snow. Fog. Have I missed anything? If weather systems were baked goods, this one would be an Everything Bagel.* As I write, the squall line stretches from eastern Indiana all the way down to south central Louisiana and out into the Gulf of Mexico, and it is progressing eastward, continuing to generate high winds, tornado warnings, and flash floods. All in all, quite an active day for this waning February, particularly considering how far north convective weather has occurred. In the face of this winter's record-breaking snow and cold, today has been a potent harbinger of what this spring, when it finally arrives, may hold. Even here in Caledonia, we got a few rumbles of thunder, though nothing like what folks a few hundred miles south of us have experienced. The irony of it is, after this, it's back to winter again. Serious, snowy, cold winter, with no sign of a letup anytime soon. Eventually, of course, the arctic air will retreat, but not without a fight. Today was just a promissory note, a down-payment, on things to come. I'm in no hurry to collect. In fact, I'd just as soon get dumped on--seriously dumped on--just to see how much more snow we can squeeze out of this winter before a warmer pattern sets in. We've already experienced unreal; let's shoot for insane. We've come this far, so what the heck, let's do this thing right. But then--let's have spring. I'm lightning-starved and thunder-hungry. ----------------------------- * That is one of the worst analogies I've ever come up with, but I don't care. Well, I care enough to write this footnote, but that's all.

The Day Before Groundhog Day: Yet Another Winter Storm–and More on the Way

Today is February 1, and let's just say it: This winter is getting reeeaaaally old. Incursion after incursion of Arctic air. Snow, snow, snow. Cold, cold, cold--and I do mean cold. After Monday and Tuesday's bitter, subzero bite, these mid-twenties temperatures that have moved in feel practically tropical. Winter_Storm_02012014We're presently under a winter weather advisory, with 3 to 5 inches of snow forecast through 10:00 p.m. around here and an inch more to the south and southeast along the I-94 corridor. And it's wet snow--not as bad as initially expected, according to the latest KGRR forecast discussion, but still watery enough--and therefore heavy enough--to put added stress on flat roofs. Here's a radar image from a few scans back. Look at all that gray! I hardly ever see returns that hit 40 dBZ with a winter storm, but a bit of interrogation revealed 49.5 dBZ over US-131 with this particular scan. And it appears to be all snow too, not a wintry mix. So yeah, I'd call that wet snow. Snow Depth Feb 1 2014The thing is, this stuff just keeps coming. We all know that by now. I haven't seen a winter this snowy since 2009, maybe even before that, since . . . since . . . well, I don't know when. As you can see from today's snow depth map, there's a strip running through my area along the western side of Michigan where the snow depth reportedly exceeds 20 inches. We're not talking about how much snow has actually fallen this winter, just how much of it is presently sitting on the ground. Twenty inches. I can testify that around here, it's not hard to find places where it's nearly up to my knees. Heck, just along the sidewalk outside my apartment, the snowblower has neatly carved a minor canyon along the edge of the featureless white expanse which, if my memory is accurate, used to be what is called a "lawn." Feb 1 GFS 132-hr fcstHow about one more image? Look and groan, because all this glorious wintry nastiness doesn't look to be retreating anytime soon. You're looking at the 132-hour forecast for the surface temperature. Doesn't that look inviting, so full of hope and promise? Tomorrow is Groundhog Day, and I'm telling you right now, that little cretin had better not show his face anywhere in my vicinity or I will send him into permanent hibernation. If there's one good thing about this winter from a personal perspective, it's that it has inspired me to learn about winter forecasting. There's certainly every opportunity to do so, and plenty of incentive. So I've learned a few new terms. Try this one on for size: heterogeneous nucleation. I like that one. Or how about this: DGZ, which stands for dendritic growth zone, the temperature range between -12 and -18 degrees Celsius wherein a saturated layer produces snowflakes. Got that? I'm starting to, along with a deeper appreciation for my RAOB software program. But I'd still be glad to see all this snow and cold go bye-bye, and I'll bet I'm not the only one. Well, well . . . buck up, ladies and gentlemen: meteorological spring is on the way. I just have a hunch it won't be here March 1. It's arrival time may be delayed by snow. What about you? Are you a winter lover or a winter Grinch--or has this winter turned you from one into the other? How do you think this crazy-cold, uber-snowy weather might affect the spring storm season? Drop a comment and share your thoughts.

Christmas Day Severe Weather and Tornadoes in Dixie Alley

I hadn't planned to post today, but with the severe weather that the NWS has been forecasting for several days now already underway in east Texas and conditions ripening across southern Dixie Alley from lower Louisiana into Alabama, I thought I'd pin a few of today's 12Z NAM forecast soundings to the wall to let you see what the squawk is about. I'm focusing on Louisiana because it seems to me that, from a storm chasing perspective, that's where the best chances are for daylight viewing--not that I think there will be a whole lot of people chasing down in the woods and swamps on Christmas, but I need some kind of focus for this large and rapidly evolving event. Remember, the sun sets early this time of year. To summarize the situation, a vigorous trough is digging through the South, overlaying the moist sector ahead of an advancing cold front with diffluence across Louisiana, Mississippi, and Alabama. Shear and helicity are more than adequate for supercells and strong tornadoes, with forecast winds in excess of 100 knots at 300 millibars, 80 at 500, and 45-50 at 850, ramping up to 60 at night per the Baton Rouge NAM. I'll start with three soundings in southwest Louisiana at Lake Charles. It's obviously a potent-looking skew-T and hodograph, with over 1,600 J/kg SBCAPE and more-than-ample helicity. No need for me to go into detail as I've displayed parameters that should be self-explanatory; just click on the image and look at the table beneath the hodograph. What I do find noteworthy is the very moist nature of this sounding, suggestive of overall cloudy conditions and HP storms. This changes quickly around 20Z (second image), with much drier air intruding into the mid-levels. From there on, temperatures at around 700 mbs begin to warm up until by 23Z (third image) they've risen from 1.5 degrees C (18Z) to 5.9--a gain of nearly 4.5 degrees--and a slight cap has formed and becomes strong by the 00Z sounding (not shown). Note how the surface winds have veered, killing helicity as the cold front moves in. End of show for Lake Charles. Farther east in the Louisiana panhandle, you get much the same story at Baton Rouge, except the more potent dynamics appear later and more dramatically, with 1 km helicity getting downright crazy. I've shown two soundings here. The first, at 18Z, has a dry bulge at the mid-levels but moistens above 650 mbs, and by 20Z (not shown) it has become even moister than its Lake Charles counterpart, to the point of 100 percent saturation between 600 and 800 mbs. Helicities are serviceable but less impressive than to the west. There's a big change in the second sounding, this one for 00Z. The dewpoint line sweeps way out, and look at that wind profile! With a 60 kt low-level jet, helicities are no longer also-rans to the Lake Charles sounding; at over 500 m2/s2, they're hulkingly tornadic, and the sigtor is approaching 13. Mississippi is obviously also under fire, and I hope the folks in Alabama have taken the 2011 season to heart and purchased weather radios that can sound the alert at night. To those of you who chase today's setup--and I know there are a few of you who are down there--I wish you safe chasing. But my greater concern is for the residents of Dixie Alley who live in harm's way and aren't as weather-savvy, and some of who--despite the NWS's best efforts--may not be aware of what is heading their way this Christmas Day. Having just glanced at the radar, I see that the squall line is now fully in play. I'll leave you with a screen grab of the reflectivity taken at 1725Z. Have a blessed and safe Christmas. ADDENDUM: In watching the radar, it's obvious that the 12Z NAM was slow by an hour or so. Can't have perfection, I guess.

Looking Back to October 17: A Wild Radar Image

On Wednesday night, October 17, severe storms rolled across the South, dropping a series of tornadoes across Arkansas and Mississippi, mostly in the latter state. The SPC's storm reports show a tally of fifteen tornado reports. I'd image that the final number of actual tornadoes turned out to be smaller, as some reports no doubt were caused by the same tornado at different points along its path. A number of injuries resulted from the storms, but thankfully, no fatalities. This was the last notable severe weather outbreak of the year and about the best that the late season of 2012 could squeak out.* A glance back at this date over a mugful of Fat Tire amber ale isn't a bad way to occupy myself on this chilly November night. That evening stands out in my mind due to some crazy radar images from a tornadic storm that moved between Canton and Carthage, Mississippi. The storm appeared to be a hybrid, part supercell and part bow echo with a potent bookend vortex. It was the darndest thing. I don't know exactly what was going on with this storm, but I certainly was surprised to see such a classic hook form out of a run-of-the-mill bow echo. In the storm-relative velocity screen, captured at the same time as the base reflectivity, you can see two pronounced couplets, one for the hook and the other for the bookend. It was fascinating to watch these features evolve. And it got even more interesting. In a Facebook interchange over the images when they were brand-new and the storm was in progress, Matt Sellers pointed out the possibility of yet a third area of circulation at the interface between the forward-flank downdraft of the westerly located supercell and the rear-flank downdraft of the bookend mesocyclone to the northeast. If you look at the reflectivity image, you'll see what he was talking about. However, I don't see anything in the storm-relative velocity grab (captured at the same time) that suggests strong rotation in that area. I just see outflow pushing south-southeastward, and not all that vigorously. Then again, I'm not skilled enough at radar interpretation that I couldn't have missed some subtlety. What Matt said makes sense, and the somewhat detached blob of red behind the gust front seems to corroborate his thinking. The area in question could have seen some spinups that would never have been detected on radar. Interesting to think about. _____________________ * In terms of severe thunderstorms and tornadoes. Hurricane Sandy obviously qualified as severe weather, but not as an outbreak. She was in a separate category, and one I haven't cared to touch. Her impact was too vast, and my knowledge of hurricanes is too limited.

Things a Jazz Musician Never Hears Anyone Say

You see this? It's a rare phenomenon in Michigan called "rain" (pronounced rayn). It began yesterday as a closed 500 mb low settled in over the state, and it looks like it will be with us for a while, as the low seems content to linger. You can see a hint of cyclonic swirl on the radar. And that's not all: as I write, just a quarter past noon, the KGRR station ob shows a temperature of only 57 degrees. After a heat wave that has stretched from June into early August, with temperatures in Michigan exceeding the 100-degree mark at times, suddenly it looks and feels like autumn. Yesterday I traded my shorts for blue jeans. Even during a normal summer, that rarely happens. After a historic, severe drought that has mummified Michigan and crippled much of our nation, this steady rain and respite from the heat is beyond welcome. It is a godsend, and those of us who believe in God thank him for it. "He sends his rain on the just and the unjust"--and to the just and the unjust alike, it is a great beneficence. Next week there's the possibility of a trough digging down from Canada across the northern-tier states, with jet energy bringing the potential for severe weather in the Great Lakes sometime Wednesday and/or Thursday. But that's far from certain at the moment. The GFS has painted some wildly varying scenarios, and the most I can see right now is that both it and the ECMWF agree on troughing, with the Euro painting the more potent picture. Okay, enough of the weather. Let's talk about music. A while ago, I posted a status update on Facebook that struck me as pretty funny. I have a great appreciation for my own sense of humor, which is a good thing because it means that I have at least one fan. What I hate is when I tell a really hilarious joke and then I don't get it. Then I have to explain the punch-line to myself, and that just ruins it. Fortunately, that doesn't happen often. Most of the time, I break out into spasms of laughter, and people look at me oddly, and ... getting back to my Facebook post: I figured that I'd share it here and then add onto it whenever I feel inclined. Feel free to post your own additions in the comments section. Without further ado, here are ...

Things which, as a jazz musician, I have yet to hear someone say:

. "Could you turn up the volume? You're not loud enough." "For our first dance, we want you to play 'Giant Steps.'" "You want $100 per musician to play at my club? Is that all? I'm doubling your rate. It's about time you musicians gave yourselves a cost-of-living raise." "First tahm playin' hyeer at the Eyegouge Saloon, eh? Well, I hope yew boys play a lot of Ornette Coleman. Folks hyeer get mighty disturbed if'n they don't get their Ornette. And another thang: do NOT, if yew value yer life, play 'Free Bird.'" "I know we're an all-white church praise team with three guitars, but we only like playing in the flat keys." "What t'hell you mean, you don't have a trombone player? How can a jazz band not have a trombone? Tell you what: you come back next week with a trombone player and I'll shell out an extra hunnerd-fifty bucks."

Saying Good-Bye to July

Looks like I almost let July slip by without making a single post. Almost. I just haven't felt inspired to write in this blog lately. Weatherwise, what's to say? Right--the drought. Frankly, I haven't felt like writing about the drought. We all know how horrible it has been: day after day and week after week of relentless, rainless heat. No doubt that's newsworthy, but I'll let the news media tackle it. From my perspective, it discomforts me, it annoys me, it inconveniences me, and certainly it concerns me, as it should anyone living in the continental United States. To say it has been disastrous is putting it accurately. But while I suppose this drought is severe weather in its own way, it doesn't interest me the way that a thunderstorm does. Mostly, it's something I wish would go away, a sentiment shared by millions of Americans roasting in the Midwestern heat. Fortunately, it won't be here forever, and lately the pattern around the Great Lakes has seemed to be nudging slowly but progressively toward a stormier one. As I write, the radar screen for Michigan looks like this (click on image to enlarge it). I like that: a cold front dropping out of the northwest bringing a nice line of storms and a good dousing of much-needed rain. Shifting gears to music, there's not much to say on that topic either. Of course I've been staying on top of my instrument, but that's par for the course. My woodshedding on "Giant Steps" and "Confirmation" continues, along with "Ornithology," and I'm getting to where I'm starting to shred the bejeebers out of those tunes. But, mmm, yeah, okay, so what. Where do I go from here? The studio, I think. It's about time I finally recorded my efforts, put something down for ears besides mine to listen to. Otherwise, why am I bothering with all this practicing of tunes that no one is ever going to call for on a gig? Folks want "Satin Doll," not Coltrane changes. Still, somewhere out there I think there are people who will take an interest. So I need to get with my buddy Ed Englerth in his Blueside Down Studios and make some noise. 'Scuze me if I sound a bit cranky. At 56 years of age, I'm rapidly approaching full curmudgeonhood and I am getting in practice for it. The lack of heavy convection and lack of gigs combined is assisting the effort. But a shift in either aspect of that equation will restore my humor and give me something to write about. No, that's not right--there's always something to write about. What I need is something I feel like writing about. Maybe later tonight will do the trick, when that storm line which is presently 50 miles to my north moves in. Hmmm ... the cell that is just making landfall near Pentwater is packing straighline winds of nearly 70 knots. That'll create some interest for folks south of town. Now to close up shop and see what kind of action we get around here a few hours hence. If it's nothing more than a good dumping of rain, I'll be more than happy. But I'm betting it'll come with a spark and a growl.

April 3, 2012, Dallas Tornadoes and a 1974 Super Outbreak Retrospective

Now that all the excitement is over, here are a couple radar grabs from shortly after 3:00 p.m. EST (1903z) of two tornadic supercells moving across Dallas. Click on the images to enlarge them. I was on the phone with my brother Brian at the time when I took the screenshots. He, my sister-in-law, Cheryl, and my nephew, Sam, live on the eastern side of Dallas. Worried about their safety, I gave Brian a call. It occurred to me that, once the storms had passed, Brian might enjoy seeing a couple of the radar shots that had prompted my concern. The storms fired when moist, easterly surface winds collided with an old, eastward-moving outflow boundary. There's plenty of lift and helicity in that combination, and with good instability and adequate upper-air support, supercells and tornadoes were the result. The event was extremely well-covered, as you'd expect when a major city is in the crosshairs in this age of live streaming and hi-def camcorders. Facebook was abuzz with chatter and images as the scenario unfolded. But it's all finished, and now we wait for official surveys to fill us in on the full scope of storm damage. From the videos and photos I've seen, some of the tornadoes were quite large, but for all that, it sounds like their impact was relatively minor. Of course, in the neighborhoods where homes got damaged or destroyed, it was calamitous, but considering what could have been, Dallas suffered a flesh wound, not a severed limb. So far I haven't heard reports of any injuries or fatalities; let's hope that continues to be the case. One irony of this event is that it falls on a date that affords ample grounds for comparison. Thirty-eight years ago on April 3–4, the infamous 1974 Super Outbreak claimed 319 lives, a figure only recently surpassed by last year's devastating April 27-28 Super Outbreak. One hundred forty-eight tornadoes raked a thirteen-state region in the East and South, and out of that number, six tornadoes were rated an F5 and twenty-four, an F4. Even the 2011 Southern Outbreak, violent, deadly, and prolific as it was, didn't rival that statistic, although it certainly came very close. Dallas today saw nothing like the disasters that unfolded back then in Xenia, Ohio; or Brandenberg and Louisville, Kentucky; or Monticello, Indiana; or Guin, Alabama. That's a good thing. Such benchmarks are not the kind you ever want your own town to challenge, particularly if your town is as large and populous as Fort Worth or Dallas. If you want to get a fascinating and gripping retrospective on one facet of the 1974 Super Outbreak, spend a little time listening to these recordings of the blow-by-blow radio reportage from WHAS as the Louisville tornado moved through the city. Or for a really eerie experience, turn up the volume and listen to this MP3 of the Xenia, Ohio, tornado as it approached and ultimately destroyed the apartment of a Xenia resident, who wisely abandoned his cassette recorder to seek shelter in the basement. And that's enough of that. It's time for me to pull away from the computer and go practice my saxophone.

March 15, 2012, Dexter and Lapeer, Michigan, Tornadoes

Thursday's tornadic supercells in eastern Michigan took a lot of people by surprise--NWS and media meteorologists, the SPC, storm chasers, and certainly me. Nothing about those anemic mid- and upper-level winds suggested the potential for even weak tornadoes, let alone significant ones. But there's no arguing with Nick Nolte's fabulous footage of the Dexter tornado, and certainly not with the damage that storm did as it swept through the town. It has been rated an EF-3, the most damaging of the three tornadoes reported on March 15, 2012. Second in impact was a tornado that struck farther north in Lapeer, causing EF-2 damage; and finally, an EF-1 tornado in Ida. Like every other chaser in Michigan whom I know, I had no plans for chasing storms Thursday. True, temps were in the 70s and dewpoints in the 60s; MLCAPE was in the order of 3,000–3,500 J/kg; and the hodograph looked curvy. But curvy alone isn't supposed to cut it, not when the dynamics are as puny as they were: winds around 20 kts at 850 mbs; 20–25 kts at 700 mbs; and 25–30 kts from 500 mbs on up to around 26,000 feet, where they finally began to make incremental but hardly impressive gains. The storms that formed should have been popcorn cells that quickly choked on their own precipitation. But they didn't. At least some of them became classic supercells that lumbered across eastern Michigan at around 15 miles an hour, spinning up strong tornadoes. I was sitting in my living room editing a book manuscript shortly after 5:00 when I happened to glance out the window and saw some impressive, well-formed towers to my southeast. "Dang!" I thought. "Those look nice!" My second thought was to grab my camera and snap a few photos. After all, thunderstorms just aren't something you normally see on March 15 in Michigan, let alone such muscular-looking ones. You can view one of the three shots I took--the last one, time-stamped 5:22 p.m.--at the top of the page. (Click on the image to enlarge it.) Curious, I took a look at GR3. I'd been glancing at it off and on as the afternoon progressed, watching a small squadron of cells pop up across southern and eastern Michigan. They resembled something I might normally see in July or August. But now, one of them looked different--so unexpectedly different that I had a hard time believing what I was seeing. South of Howell and northwest of Ann Arbor, the most vigorous-looking storm of the bunch had transformed into an unmistakable supercell--a regular flying eagle with a little pinhole BWER in the hook. Where the heck did that come from, and why on earth was it there? Pinch me, I must be dreaming. I switched to SRV, and sure enough, there was a couplet, and not just a weak one, either. A pronounced couplet. A scan or two later, the storm was continuing to develop. The pinhole had disappeared, and the supercell now had a classic hook. On radar, it looked as nice as anything you could hope to see out West in May--only this was Michigan in mid-March. Surely the winds had to be better than I had been led to believe. One way to find out. I pulled up the VAD wind profiler at DTX. Ummm ... well, okay. Nothing at all remarkable there. Maybe, given the curviness, enough bulk shear to organize the storm. Obviously that had to be the case; the evidence was staring me in the face, along with a couplet which hinted at the tornadic action that was presently occurring. The last screen capture, just below and to your right, shows both the couplet and the VAD. Enlarge the image, zoom in on it, and you can see for yourself just how meager the winds were and why one would expect storms forming in that environment to drown themselves in their own tears. While I was glued to my radar in Caledonia, across the state storm chaser Nick Nolte was hot on the storm and videotaping the tornado that eventually hit Dexter. After getting out of work for the day, Nick had noticed the storm popping near where he lives. Grabbing his gear, he took off on what turned out to be one of the most serendipitous chases any chaser could hope for. Nick got some fantastic footage of the Dexter tornado. Congrats, Nick--you really nailed it! Rather than steal Nick's thunder by embedding his YouTube video here, I'm going to simply redirect you to his site and let you hunt it up there. I've viewed some other footage beside Nick's that demonstrates a particularly noteworthy aspect of the Dexter tornado, and that is its breakdown into helical vortices. I've seen only one other video that demonstrates this helical structure so clearly, and that is the famous KARE TV helicopter video of the July 18, 1986, Minneapolis tornado. The Dexter footage isn't as dramatic, but it nevertheless depicts the helical effect with stunning and captivating clarity. Nick's video captures it as well toward the end of his clip. It's really amazing to see. Unfortunately, the Dexter and Lapeer storms did considerable damage. If there's a bright side to their human impact, it's that no one was killed or seriously injured. What turned yesterday's anemic setup into a significant tornado-breeder? A weak upper-level impulse provided the needed lift to spark the storms, but it doesn't explain why some of them developed into tornadic supercells, given the lackluster mid- and upper-level winds. I'm no expert, but I'm guessing that the unseasonably high CAPE is what did the trick. I suspect it took what was present in terms of shear and helicity and amplified it, in effect creating the Dexter, Lapeer, and Ida storms' own mesoscale environments--ones conducive to tornadoes. Of course, similar scenarios typically provide no more than single-cell and multicell severe storms. But then, yesterday was an anomaly in some significant ways. After all, this is Michigan, and it's only mid-March. When CAPE of that magnitude shows up in the midst of unseasonably high dewpoints, it appears that all bets are off. ADDENDUM: Lest you should miss reading the comments, check out this satellite loop from Thursday. You can see the storms exploding along an outflow boundary pushing west-northwest from Ohio, and other storms firing along a cold front dropping southeast. Two boundaries, and they actually appear to collide around Saginaw. The OFB accounts nicely for convergence and low-level helicity. Thanks to Rob Dewey for sending me the link.