Monday, June 27, 2005

another radio interview...

i suppose i didn't say how the other one went, but i can say that the cbc interview went just fine. i got out of my air-conditioned car and my glasses fogged up because of the 25 degree dewpoint air. man, was it ever steamy! the studio was nice, and marilyn was a good interviewer. the segment was approximately 10 minutes long, and we took 2 calls before we had to wrap up.

wednesday, june 29, i'm scheduled to do an interview with cbc saskatchewan. about 12:10 pm cst, or 1:10 manitoba time. should be good--lots of people to talk to about all the recent severe weather they've had there, including the 2 tornadoes i saw near cadillac.

here's hoping we get even more attention about the course!

Sunday, June 26, 2005

sitting idly...

the reason i'm here at home blogging instead of out chasing is because i'm moving on tuesday. i have to finish packing and whatnot, so the only way i'll be able to go out chasing over the next couple of days is if it involves something fairly close to winnipeg--what's often called a spot chase or a gentleman's chase. (i'm not trying to be sexist--that's what it's called.)

today my target changed a bit, but had i gone chasing i would have been in the right general area and would have had time to make it there. it's now clear that the area south of jamestown, nd is primed for supercells--possibly tornadic. there's a warm front lifting slowly northward through the area. with peak heating and abundant moisture and shear, well, things should blast off in extraordinary fashion. in between taping up boxes i'm coming back to my computer to check and see if it has gone yet. as of this writing, the first storm seems to be going east of mobridge, sd, just south of the warm front. as soon as it hits the front it could do one of two things: it could either cross the front and keep going, becoming slightly elevated and maybe a hail producer, or it could turn hard right and have a tornado on the ground for 2 hours.

another area of potential concern is, oddly enough, the southern red river valley. cirrus blowoff from overnight convection has limited the amount of sunshine over southern manitoba, but despite that, temperatures have still made it into the mid-20s, providing for a very healthy 2000 j/kg of sbcape. locally backed winds due to i don't know what could provide enough shear for any storm that pops up to become a supercell with a chance of low-level rotation. we're not talking long-lived tornadic supercells here--at least i don't think we are. not like in southeastern north dakota, anyhow.

i have to keep reminding myself that we're not yet even at the peak of the traditional season around here--we're still in the early stages! actually the first sign of approaching the peak season came to me today--i smelled the evapotranspiration from canola crops when i went outside. if you don't know what it smells like, let me try to describe it to you: it's sort of like an inoffensive, slightly sweet skunk smell. i'm not kidding. when we're out on the road and encounter it (and trust me, we will!) you'll decide for yourselves what it smells like to you. but i like my description.

whatever its description, it means the moisture is here to stay. bring on the storms!

Thursday, June 23, 2005

this evening's presentation

okay, that wasn't the best presentation i've ever given. far from it, in fact.

i hadn't had the time to prepare for it before last night, and then today had more going on (non-meteorologically speaking, that is) than i had expected. so i apologize for the presentation being a bit disjointed.

the good news, though, is that you all seemed to get the main points of what i was getting at. and that's pretty much all i can hope for.

we'll likely be doing more miller workups later on in the course and, if not then, while we're out of town.

now to go put today's presentation on the website....

interview about the course today

sometime between noon and 1 pm today, june 23 2005, marilyn maki will interview me on cbc radio. this is to be about the storm chasing course. cool. now we'll have more publicity.

that can't be a bad thing. :)

Wednesday, June 22, 2005

busy night!

last night a tornadic supercell just missed lethbridge, ab, and moved to the east-northeast, crossing the border into saskatchewan near schuler. it continued to produce severe weather, eventually morphing into a bow echo with maximum measured winds of 150 km/h! there was apprently quite a bit of damage in leader, sk from these winds. as well, there was baseball- to softball-sized hail in eastern alberta.

which wasn't my target area.

i wasn't chasing, however. paul and the college of dupage crew were chasing.

we talked this morning about target areas, and we all agreed that western sk, west of swift current, would be the place to be. well, we were wrong. the huge supercell began in south-central alberta and didn't allow for anything else to take over.

when i talked to paul last night, he and the crew were on their way back to regina with their tails between their legs. they had expected, like we at the office had, that storms would fire up even more vigourously in the convergent area near maple creek. we were wrong.

paul was near tears.

i mean, our mantra here is that severe weather is bad. and it is. but really, we're here to chase and see beautiful thunderstorms, the most beautiful of which, to me, are supercells.

but severe weather does bad things. personally i'm not a big fan of being caught in an 80 knot wind gust or being pummeled by softball-sized hail. (and yes, both of those things have happened to me!) this could lead to an aside about how i can be happy to see a beautiful storm structure when that same structure can cause so much grief. well, you can check out what chuck doswell has to say about it, because i wholeheartedly agree with him. but in a nutshell, i can't change the fact that severe weather is coing to happen. i can therefore contribute to the safety of others by safely viewing these storms and warning others as to their whereabouts and what they're likely to do. it's just a side bonus that i find them so beautiful. ;)

last night i was hoping to get work done on thursday's presentation about the miller technique. but i was too busy interpreting radar signatures, giving advice on bulletins, and taking severe weather reports. so if i don't have it done in time, now you know why. ;)

i just feel so badly for paul. 4 trips this year and not a single tornado yet.

i think he's starting to believe that there's no such thing as tornadoes.

would that make it the tornado claus(e) or the non-tornado claus(e)? :)

Sunday, June 19, 2005

a successful chase

i got up on friday morning, intending to go to regina. i did that, but along the way wxdog steered me toward moose jaw, both because they have a great library there and because, according to him, the threat had shifted farther westward.

i got to the library and agreed with him. the question was, where exactly? there was great 0-6 km shear, there was lots of moisture and instability, but there wasn't yet a focus for the convective initiation. that's an important one. if you're looking for where they'll start, given a favourable environment, you need to find a focus, usually in the form of convergence--a dryline, a warm front, a cold front, a subtle wind shift, an outflow boundary--anything.

i meandered to swift current and stopped in their library (after taking about 20 minutes to find it, despite good directions) and i finally found the focus. just to the south of me, the wind shift line had sharpened up quite a lot. south of the boundary the winds were from the sse. north of the boundary they were almost due east. this was good. so i decided to take off south out of town based on that and also based on the fact that visible imagery showed a persistent cumulus field in the area, indicating enhanced lift. a tornado watch was issued for the area. (and btw, i came back here to find out an extreme rarity--the paspc had issued a high risk of severe thunderstorms for the area.)

as i left town i noticed storms starting to fire up straight ahead of me. i got south as quickly as i could, and i was greeted by a slowly strengthening thunderstorm with a ragged wall cloud underneath the southern flank--right in the right spot.

i called in my report of how it looked, and told them i would be watching it.

soon, the storm's wall cloud started to show marked rotation, a fact i relayed to the office. i told them that the rotation was tightening up, and that the right side of the wall cloud also had fairly violent upward motion on it.

15 minutes later this wall cloud dropped a funnel about halfway to the ground. again i called it in. (i think they may have been sick of hearing from me. ;) ) it's at this point (i think) that a tornado warning went out. soon enough, it dropped a brief tornado--it lasted maybe 5 seconds--and it went back into the cloud. the whole system was moving to the north, so i kept creeping in that direction. at the time i was near cadillac, sk. soon the wall cloud dissipated and started moving quite a bit north of my location, so i tried to reposition in that direction.

bad idea.

i got into some rain and small hail, and the wind was strong out of the north--indicating that i was in the outflow of the storm. a little farther north, though, the wind suddenly shifted to the east.

uh oh.

my spidey sense was tingling (okay, my conceptual model of a supercell was) and it told me that if this thing decided to drop a tornado, i could be in its path.

good move, dave.

as soon as i had turned around, my phone rang--it was a-pry. she said something along the lines of "good, you're alive". huh? soon enough, though, i saw why she was concerned.

as i got into the lighter precipitation, i saw something to my east. yes, it was a tornado on the ground. a pretty big one, an elephant trunk. had i kept going north then east, like i had been intending, i would have been directly in its path. this tornado ended up doing some damage in and near the town of neville--roofs damaged and the like.

this point here was a learning experience for me--a bird in the hand is worth two in the bush. or put otherwise, a tornado right in front of you is worth much more than repositioning for the possibility of a later one. too bad for me i had yet to learn this. i kept driving, trying to get into better position to see the next tornado this storm would produce. as it turned out, though, that would be the last one i would see that day. the road network out in southwest sk is not conducive to storm chasing, unless the storms are right near the path of a good roadway.

i drove around the area for the next while, trying to reposition myself and getting in between supercells, so i put down my tripod and caught another wall cloud and possible funnels (i haven't examined the tape yet) near shamrock.

then i went into the town of shamrock and learned another lesson. not the hard way this time, though. luckily. a wall cloud was sse of me and i wanted to get a look to see if it was putting down a tornado or more. all i had was a gravel road, though. a gravel road that had, in the previous half hour, received about 50 mm of rain. you can see where this is going.

the driving all of a sudden seemed mushy and slippery, kind of like driving on a sheet of ice covered in 2 inches of snow. i decided the best course of action would be to stop then and there. good move. i backed up out of there, very slowly, not even trying to turn around. the road was about 6 inches of mud where i was but had i gone farther it would have gotten much worse. as it was i was hubcap-deep in mud, and that was good enough for me. luckily i made it out of there without further incident.

i finally got into moose jaw around 11 pm local time. since the cell phone coverage wasn't very good, i hadn't been able to phone ahead to book a room for myself. (note to self; book ahead!) i think i got the last room in town. 69 dollars. actually, it wasn't bad for late friday night in early-mid season.

like mom always made me do when i was bad, i went to bed that night without any dinner. and that's really too bad, because i should have had the traditional storm chasing tornado celebratory meal: steak. for the vegetarians out there, i don't know what to say. perhaps you could suggest an alternative? and btw, it's bad form to have steak while you're on a chase and you haven't seen a tornado--it's considered a jinx. ribs, fine. burgers, fine. pretty much anything else, fine. but have steak on an unsuccessful chase, and you're likely in for some ribbing. pun definitely intended.

saturday looked pretty good, too, over southwest manitoba. since that was in the direction of home, i decided to go chase around there.

i got to virden around 1 pm and things were still well capped, so i stopped in for a library break. again, great library. it would be nice to have data on the road rather than only at select stops. but i digress.

i left the library and decided to play the southern end of the cumulus field. convergence and upper cooling were to be coming in, so it looked like the sweet spot.

wxdog called me and told me some americans--including tim samaras--were planning on chasing the area today. about 4 seconds after he said that, i was passed by a couple of vehicles with colorado plates, and one of the plates said "strmchsr". hmm, i wonder who that could be. ;)

when they stopped on a side road, i stopped, got out and introduced myself. we chatted for about a half hour and then i decided to drift to the northeast and meet up with paul and the gang from college of dupage, who were in brandon.

we drove around for a long time, wondering if things would go at all. finally, near pipestone, storms started going along the convergence line. good deal. we went off in that direction and got deflated. the storms were briefly pulsing up and then dying. what the? there was plenty of instability and shear. why were they not going huge?

at about 7 o'clock we took off to the east for a gas and bathroom and disappointment break in souris. after coming back out of the store, we noticed much stronger towers to the west. paul has an internet connection in his van, so we could see it on the minot radar. it was starting to have a kidney bean shape, typical of a supercell, so we decided to go back west and check it out.

when we got there it was already impressive. definite supercell with good mid-level rotation on it, and a somewhat ragged wall cloud. i called the paspc and told them what i saw. soon after, based on what i was seeing (at least a little bit) but mostly based on doppler radar, they issued a tornado warning for it. paul and the gang headed north and i followed them. no, dave, next time listen to yourself. i thought that this storm would be crossing the highway before the next road and would get us stuck, and i was right. i got quarter-sized hail in the storm and decided to turn around--and go back south slowly. i didn't want to be driving blind into a tornado.

well, it never did end up putting down a tornado. i think it's probably because, with everything else in place, the winds at the surface were just too wimpy. in the storm environment they were light out of the se. i wanted 20 knots from straight east. then i'd probably be telling a different story here.

but still, it was a beautiful storm. i got lots of pictures of it, mostly of the wall cloud but also of the mid-level mesocyclone and the towers going up. i hope they turned out well.

as i was heading home east of brandon, i looked in my rear-view mirror and saw that the storm had reintensified, so i stopped and took some pictures. the wall cloud it was making at that point only lasted for about 10 minutes and then dissipated.

i put 2100 km on my car in 2 days. extremely tiring. i don't know how i'm going to manage driving like that for 5 days straight.

maybe i should just hope the storms aren't very far away. ;)

Thursday, June 16, 2005

i can't ignore this one

well the setup is great--almost too good to be true, actually.

tomorrow i'm going to regina. the pattern looks ridiculously good for supercells and tornadoes, somewhere between regina and wynyard.

a warm front is progged to lift northward to lie in the area. moisture will be plentiful--it's already in place--and the shear near the front will be great. as well, if anything develops tonight, there could be a remnant outflow boundary to help things, like there was just outside of hill city, ks last week.

wish me luck!

Wednesday, June 15, 2005

or maybe not...

okay, well maybe things aren't going to be such a slam-dunk tomorrow. to that end, i might not end up going chasing then.

saturday's setup is looking great over the nd/mb/sk border area. it's of course based on model runs, but that's all we can use right now. with the flow and the moisture in place now, though, it's not a matter of if--it's a matter of when.

Tuesday, June 14, 2005

to go or not to go...

i have off until saturday. i'm wondering if i should go chasing.

the southwest storm chase flow is stil being progged to set up over the prairies tomorrow and then until who knows when. so now with the heat getting into place it'll be a matter of moisture, shear, and timing of any wavelets coming through the flow.

when to go? i've been told to trust my instincts (i.e. my meteorological knowledge) and right now thursday looks better than wednesday. i'll check on things before going to bed tonight, but you can pretty much bet i'll be going chasing later this week.

Sunday, June 12, 2005

major chase site update

i've made a major update to the weather central chasing page. i know, it looks a lot like the weather central information page--and it is. i just poached the code from the latter and put it into the former, with a few minor changes. i plan to tighten it up a little over the next while, but it'll be a slow process--this is the first time we're offering this course, so it's difficult to say at this point what's useful and what's throw-away-able. yes, i know it's not a word. yet. i'll call the dictionary people.

if you have any suggestions about weather central, about any of it, please email me. the email link is at the bottom of just about every page on there, so it shouldn't be hard to find. it's not my weather central, it's yours. make it more so.

it figures--right now the model runs are pointing to a relatively quiet few days, thunderstorm-wise. that is, until i go back on shift. then, they light the skies up.

okay, that's not completely true. the current day 4 forecast from the gem global is showing an outbreak scenario over west-central saskatchewan, and the next day over southwest manitoba. but the gfs is showing much more benign weather unitl next weekend.

but one thing they're agreeing on is that a southwest flow will be setting up over the northern plains and the prairies by the middle of this upcoming week.

which means, of course, that it won't actually happen. ;)

Saturday, June 11, 2005

just a thought..

i've never seen an lp supercell before. at least, i dont think i have.

i've seen a lot of other meteorological phenomena; however, that one eludes me. do they happen on the prairies? i suppose they do.

but i wonder how long it'll be before i see one like the kind shown on the storm chasing websites, like eric nguyen's page.

of course, a tornado would be nice, too. ;)

dereliction of duty

i posted yesterday (actually the day before) that i would post images from the gretna event.

well, i didn't get to it, due to some things that popped up. (they always seem to do that, don't they?!) but the images from the gretna event (or non-event, as it now seems), as well as some other interesting ones, should be on weather central within a few hours.

meeting the class for the first time was good. now hopefully i'll be able to remember all your names. give me some time to do that, though--especially since my next appearance in the classroom will be june 23. ;)

Thursday, June 09, 2005

tornado yesterday in gretna?

i was chatting with a-pry yesterday afternoon before the excitement hit (more on that later) and she mentioned that she thinks i'd make a good teacher. i had just given her and one of the other students a tutorial on doppler radar. and you know, i don't know if i'd make a good teacher, but i sure know i like to teach. i suppose that is, in part, why i agreed to be an instructor for the course.

yesterday afternoon the persistent cloud cleared out of the far southern edge of the province and thunderstorms almost immediately popped up. one storm was in north dakota and very close to the international border. radar was showing severe hail with the storm, so we decided to issue a severe thunderstorm warning for it. well, a few minutes later, i get a call from nws grand forks, telling me that law enforcement was reporting a tornado just southwest of gretna on the american side, heading pretty much straight for gretna. we immediately issued a tornado warning.

a-pry will likely be trying to track down whether or not it was on the ground in canada, but there was certainly some severe weather with the storm. there was hail at least the size of quarters (25 mm) and possibly up to the size of golf balls (40 mm). time will tell.

one of the most interesting things about this storm, though, was the fact that doppler radar was showing anticyclonic rotation inside the storm. conventional wisdom has it that about 1% of all supercells rotate anticyclonically, and even fewer of those produce tornadoes, so we apparently had an extreme anomaly yesterday. i'm glad to report that i captured some of the radar images and they should be posted sometime today on weather central. enjoy!!

Wednesday, June 08, 2005

a few days later

i know it's a little bit schadenfreude of me, but perusing the chaser forums online shows me that there were a lot of chasers in kansas who busted on saturday. so maybe it's not making me happy, but at least a little less disappointed--misery loves company.

on another note, there's a lot of buzz on the same forums about this coming weekend in the southern and central plains. spc has already issued a moderate risk for friday, and according to the gurus the entire weekend looks classic.

i have 2 problems with this.

first off, it's all a model forecast. i've come to distrust models immensely. for example, the current forecast for saturday, based on a model, says "periods of rain". yesterday's forecast for the same day, based on a prior run of the same model, said "sunny". there's more flip-flopping going on here than a pair of thong sandals.

second off, i worry now about high cape/high shear days. the storms move really quickly and if you don't get the proper backing of the winds, you could be chasing your own tail and busting along with 100 other chasers. or you could have a supercell bearing down on you at breakneck speed. the potentials for a bust chase or for a busted windshield are high.

all that being said, i will be watching things closely this weekend to see how it all plays out.

props to eze for capturing radar and satellite images from my bust chase day. i'll be posting them on weather central soon.

Saturday, June 04, 2005

on the road chasing...

something chuck doswell wrote a couple of years ago is ringing true to me. that is that meteorology is the same no matter where you go.

not a profound statement, i know, but hear me out.

people say to chuck all the time that he's "so lucky to live in oklahoma because the storms there are so much more (fill in the blank)". well, i think that's a load of bullplop.

today we busted bigtime. i'll get into that in a little bit, but i want to flesh out my first point right now. with the chase bust, though, i saw a lot of formations in the sky, a lot of motion, a lot of dynamics. this is, however, no different from anything i've ever seen while chasing in the dakotas or the prairies. no better and no worse. not more impressive, nor more explosive. meteorological science holds up all over the earth, and if you have the same ingredients coming together, whether you're in enid, oklahoma or tuktoyaktuk, northwest territories, you're going to see similar things.

now to the chase bust.

things looked good today. we were under a high risk of severe thunderstorms according to the spc. the high risk included a fairly solid shot at some long-track violent tornadoes. from my analysis i had 2 concerns: 1, that when the storms fired up, they would be moving fairly quickly--the tropospheric winds were such that any storm would move at about 35 knots, or 65 km/h. that's fast. 2, that the surface winds in the zone of terror were not backed, that is, more southeasterly or easterly as opposed to the southerly that they in reality were, and my concern was that this would lead to more linear formations of convection, rather than discrete storms with persistent rotating updrafts.

well, we busted. the winds didn't back enough. there was little cap. there was too much lift and cape. looking back on it, hindsight being 20/20, i should have played the cape vs. shear game--in which it seems the shear almost always wins. i busted in june of 2003 over manitoba and north dakota because of pretty much the exact same thing. so next time i play the cape vs. shear game, remind me that shear seems to win out.

by the way, this was my first real experience with chaser convergence. i think i saw a total of 100 chasers, maybe more, over the course of the day. 100!! the most i'd ever seen before in one day was about 25--when the college of dupage and the verkaiks met up in davidson, sk, with myself and a group of colleagues from toronto.

so what did i learn today? trust my own forecasting skills. i let paul influence me a bit too much today, partly because i have so little experience in the central plains, and partly because i **wanted** a high risk over the area, even though in retrospect it looked not all that great.

tomorrow, i'm on shift. because of that, there's a moderate risk over eastern south dakota.


well i guess there'll always be more storms. they just seem so few and far between these days.....

nervous anticipation

i'm back in that same library in wichita.

there's a high risk today. a high risk of severe thunderstorms. the southwest edge of it is here, and it extends to northeastern kansas and southeastern nebraska.

i've never chased a high risk, but i'll be in one today.

this will take extreme care--days like today can be very dangerous if you're in the wrong place, so driving and keeping my head on a swivel will be of utmost importance.

keep your fingers crossed....

Friday, June 03, 2005

long trip, no dice so far...

i'm writing this from the public library in wichita, kansas. yes, kansas. i got off night shift yesterday morning and slept till 1, then took off and drove to sioux city, ia (actually, north sioux city, sd). today was looking good, then okay, and now pretty much not.

today had looked spectacular, a couple of days ago, according to the models. i had pinpointed my target area as somewhere in the box outlined by salina and topeka, kansas, and by lincoln and grand island, nebraska. things have changed a bit.

the moral of the story here? analyse, analyse, analyse. and when you're done with your analysis, do more analysis. the models steered me wrong today. let's just hope that they're a bit more on the ball for tomorrow with respect to the potential major outbreak between here and topeka.

the college of dupage guys are right now down in central oklahoma. there's a tornado watch box up there right now, but it's not worth it for me, although i think i will make the 1 hour drive to the border just to say i was in oklahoma.