The Tornadoes Are Over but the Malady Lingers On
July 27th, 2009 at 1:47 pm by Don Paul under Weather Watch 4
Still another in a long series of unsettled weeks coming up. The upper trough continues to be in a favorable position to send a series of short waves in our direction, after such an active severe weather day on Saturday and somewhat less active day on Sunday. Early indicators don’t show much in the way of severe weather potential this week, but hydrological issues may come into play with such saturated soils and high-running creeks. Even the 2 days which looked to be essentially dry back on Friday–Monday and Tuesday–have modest chances for isolated convection, with more widespread activity developing on Wednesday, and another disturbance getting here on Friday. Tuesday will include a warming trend with some downsloping to begin with. However, it’s harder to heat the boundary layer when the soil is so wet. At least an early look ahead to next weekend–while not a lock–looks mostly promising.
Hvy Shwrs making their way across nrn Niag Co.
Those heavy (very!!) showers, with thunder are now here in southern Welland (southern Niagara peninsula). Started about half an hour ago. Appears that they may continue for a bit yet? Enviro. Canada issued a t-storm watch for n. & s. Niagara peninsula (Ontario).
MC
I guess I spoke too soon…there’s a heavy batch of t-storms moving over N. Tonawanda headed directly for Pendleton/Lockport. I had seen a lot more north/northeast movement to this rain earlier, but the t-storm in question is definitely moving almost due East. Time to watch the yard flood again…
Here is an AMAZING phenomenon reported by the Milwaukee NWS, on cumulus forming more quickly over hail damage swaths, with a good explanation. DEFINITELY worth a looksee, folks!
http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=mkx&storyid=29983&source=0
Don,
This is a great example of how the local agriculture can (and does) have a dramatic effect on local climatology/weather. There’s some fascinating research on the Midwest winter wheat and corn crop that covers this phenomenon, but rather than a complicated article, I suggest for an easy read (got to page 10):
http://www.crh.noaa.gov/images/ict/newsletter/pdf/Fall2007.pdf
This also explains why forecasters across the NE tend to slightly underestimate high temperatures during unusually warm periods around the April timeframe (little evapotranspiration processes). Forecast models, including numerical guidance (MOS or model output statistics), will consistently underestimate these warm events as they don’t factor in this important part of the water cycle in well and lean more toward climatology. With dormant trees and no agriculture during (mid) April, we are essentially living in a desert-like environment (with a rather dry airmass). It’s our fire season, and it lasts about 2 weeks until the trees start taking in water.
Conversely, models and some forecasters will tend to (less often) overestimate high temperatures during the hottest days of the summer, as much more moisture is being released to the atmosphere by plants/trees providing a subtle cooling effect. This is more common during/after wet periods. Can anyone think of recent example of this?
With these scenarios, models don’t take into account the extra amount of low level moisture from soils, plants, and trees. Aside from temperature verification being off by a few degrees though, many would not notice these subtle temperature forecast “busts” as the extra moisture just makes the air a bit more humid.
Anyway, cutting corn, wheat, hay, etc can have a local effect on temperatures, adding to the ‘chaos’ in the atmosphere. Thanks for bringing this neat phenomenon up!
On a different but hey-that’s-cool topic (get it? ‘hay’ and ‘cool’), here’s a neat link showing the solar eclipse shadow from last week:
http://cimss.ssec.wisc.edu/goes/blog/archives/3020
Seattle hit an all time high of 103 today, and Portland hit their all time high at 106–while the NE chills, the NW sizzles.
A) Let it stay in the NW!
B) REALLY interesting article about the hail damage and diurnal heating.
Seattle can keep those kinds of temps!
“But it’s a dry heat!”
In Seattle, it can only get truly hot when there’s an offshore flow, similar to what occasionally happens in SF and more often happens in LA. That flow always present low dewpoints.
But I’m sure glad it wasn’t 106 when my AMS conference was going on in Portland last month(we were in the 60s and 70s most days).
Seattle could use the warm weather
, I’ve always thought of Seattle as being dreary and 60F most days during the summer, though according to this article, New York (of all the places to pick on) has higher annual rainfall.
http://www.gonorthwest.com/Washington/seattle/weather.htm
I have family in L.A. and have heard that they have been up in the 100s in recent days, so it appears that most of the west coast is in quite a heat wave right now.
Don – I found the NWS article on hail scars in Wisconsin to be incredible. Thanks for posting.
Actually, Seattle generally has very nice summers, with rainfall in most years at a minimum. Their reputation, like ours, is really tied to the colder weather months. Easterners don’t know any more about their overall climate than westerners do about ours.
I’ve lived up in Sudbury, Ontario, Canada all my life so far and I cannot recall having two cool wet summers in a row. Although we aren’t quite in August yet, I hope August will be a better month and i’m pretty sure we’ll have a nice Fall if this keeps up! We recently have had a heavy rainstorm on Sunday (July 26) and another on Tuesday (July 28) in the Sudbury’s Downtown area flooding streets, basements, sewage backups, and stranding drivers on streets. The basements that got flooded on Sunday got flooded again on Tuesday…Yikes!!! Good thing I don’t live in the area. Here’s some links of the rain and flooding:
http://www.northernlife.ca/news/localNews/2009/jul/flooding260709.aspx
http://www.northernlife.ca/PhotoGallery/07-27-09-01/index.html
http://www.youtube.com/watch?v=we7x_KRnklc&feature=related
http://www.northernlife.ca/news/policeandCourt/2009/jul/flooding_again280709.aspx
I’ve lived up in Sudbury, Ontario, Canada all my life so far and I cannot recall having two cool wet summers in a row. Although we aren’t quite in August yet, I hope August will be a better month and i’m pretty sure we’ll have a nice Fall if this keeps up! We recently have had a heavy rainstorm on Sunday (July 26) and another on Tuesday (July 28) in the Sudbury’s Downtown area flooding streets, basements, sewage backups, and stranding drivers on streets. The basements that got flooded on Sunday got flooded again on Tuesday…Yikes!!! Good thing I don’t live in the area. Here’s some links of the rain and flooding:
http://www.northernlife.ca/news/localNews/2009/jul/flooding260709.aspx
http://www.youtube.com/watch?v=we7x_KRnklc&feature=related
Seattle does have nice summers, alot of which are dryer than people think. Friends there say most homes don’t have AC since summers don’t usually get that hot so 100 degrees is currently a big problem. They are under an Excessive Heat warning until Friday plus there’s also an Air Stagnation Advisory posted for today. Not good…..but still, a beautiful part of the country.
Good stuff Lee! As for the man who said (when asked where did he think the water came from?), “I haven’t got a clue”, I think someone should tell him it came from the sky!:)
Showers moving in late tonight look to be minor and spotty on the Niag Frontier, with more persistence in the s tier/PA–but no biggie. And, some sun will return on the N Frontier by Friday afternoon. Saturday is still looking great, but Sunday is slipping with some Sct Shwrs now appearing likely. If the GFS is on the money, we may clear up in time for some Sunday barbecues.
That western heat stretches north into British Columbia with a record all time high off 92 Farh in Vancouver on Wednesday. Even the Yukon is sizzling, where the capital Whitehorse is in the lower 90’s with rare thunderstorm watches.
As I posted here last week Don, even Iqualit in Nunavut, in Canada’s southern Arctic region, there were record highs of 75 and 77 Farh.
A strange summer.
I have a physics puzzle raised by Dr. Peter Ostrow, our medical reporter and UB med school prof. He has a drainage pond behind his home nearly 1 acre in size. After last weekend’s torrents, the drain in the pond became plugged. Peter unplugged it, and the water began draining in a typical vortex–except, it started with a clockwise motion, then stopped, then renewed in a counterclockwise motion, stopped again, renewed again as clockwise, and continued this on-off-reversed circulation pattern repeatedly, over and over again. Dr. Ostrow’s question about this curious phenomenon is one I can’t answer with any kind of certainty.
First, there are myths about toilet bowls and bathtub drains being affected by the coriolis force, with counterclockwise circulation dictated by a northern hemisphere location. In actuality, the mass of the water in a bathtub, toilet, or sink is insufficient to be affected by the coriolis force, something like the mass of an egg being far too insufficient to be affected by the equinox (you can stand an egg on its end 365 days a year, if you have patience).
One question is whether the mass in a pond this size would be affected by the coriolis force and, if so, why would there be periodic reversals.
Any thoughts on this z or Yukon Jack? I admit I’m at a loss, and Peter–being the brilliant and inquisitive scientist that he is–will come back to me on the issue; of that I can be sure! And, no, I don’t know the volume of the water in this large pond even though I’ve seen it many times.
Hi Don,
Here are a couple of articles that might help answer your question regarding the Coriolis effect…
http://www.snopes.com/science/coriolis.asp
http://en.wikipedia.org/wiki/Coriolis_effect
The Wikipedia article is a bit more technical and tries to explain things in a mathematical fashion. I’m still trying to wrap my head around the math, but my first take on the subject is that the Coriolis effect is extremely weak at best, and often is not the ultimate deciding factor on the direction of the vortex of draining water. I’m not sure if Dr. Peter has read through the Wikipedia article, but I bet he would be intrigued by it. Other factors, such as the shape of the basin of that pond, probably had the most influence on the way it drained.
To further elaborate, if you read through that first article, you’ll note that it states that the Coriolis effect does not have much of an impact, if any, on small scale bodies of water, such as sinks and toilets. Even if that pond was the size of the Colosseum, it would be too small to be affected by the Coriolis effect. The shape of the pond itself influenced the way in which it drained, I think that would be a safe way to answer Dr. Peter’s question…
Well, as you saw, I already discounted the toilet bowl/bathtub drain silliness. And even Peter has the feeling, as I do, that the volume of water in this large pond is less than likely to be affected by a relatively weak force. However, we don’t know the threshold of mass/volume at which an effect might begin.
The question he’s most concerned about is why the drainage–with great regularity–continued, stopped, reversed over and over again. My guess is there’s something mechanical/physical at work in the undersurface of that pond.
Neither of us are going to rent scuba gear to find out what, though….
Agreed – yes, the bathtub/sink myth was debunked many years ago. Dr. Peter mentioned that pond drain being plugged, I’m betting the plugged up drain changed the shape and direction of the water vortex itself which resulted in the clockwise/counterclockwise rotation upon successive drainage of the water. However, I will see if I can find any information regarding the threshold of mass at which the Coriolis effect begins to have an impact.
But I’ve also learned you can’t convince some folks about the silliness of bathroom drain rotation, eggs on end, the ice boom weather effects myth, astrology, reflexology, the Farmers Almanac, and a host of topics under the category of pseudoscience. That doesn’t stop me from trying, though.
In the meantime, Sunday’s showers are still in the fcst, but it doesn’t look like anything approaching a steady rain or a violent convective outbreak. It will just be a downer after a gorgeous Saturday.
There are hints of a weakening of the troughiness in today’s NCEP 500mb ensemble mean, but not a disappearance. Steve McLaughlin at NWS estimates this will end up being the 4th coolest July for Buffalo, and coolest since the NWS moved to the airport in the early 40s.
Don,
I tried to post this a few days ago, but I it says “Your comment is awaiting moderation.”
Regarding your post on the hail damage swaths and cumulus clouds….
This is a great example of how the local agriculture can (and does) have a dramatic effect on local climatology/weather. There’s some fascinating research on the Midwest winter wheat and corn crop that covers this phenomenon, but rather than a complicated article, I suggest for an easy read (got to page 10):
http://www.crh.noaa.gov/images/ict/newsletter/pdf/Fall2007.pdf
This also explains why forecasters across the NE tend to slightly underestimate high temperatures during unusually warm periods around the April timeframe (little evapotranspiration processes). Forecast models, including numerical guidance (MOS or model output statistics), will consistently underestimate these warm events as they don’t factor in this important part of the water cycle in well and lean more toward climatology. With dormant trees and no agriculture during (mid) April, we are essentially living in a desert-like environment (with a rather dry airmass). It’s our fire season, and it lasts about 2 weeks until the trees start taking in water.
Conversely, models and some forecasters will tend to (less often) overestimate high temperatures during the hottest days of the summer, as much more moisture is being released to the atmosphere by plants/trees providing a subtle cooling effect. This is more common during/after wet periods. Can anyone think of recent example of this? With these scenarios, models don’t take into account the extra amount of low level moisture from soils, plants, and trees. Aside from temperature verification being off by a few degrees though, many would not notice these subtle temperature forecast “busts” as the extra moisture just makes the air a bit more humid.
Anyway, cutting corn, wheat, hay, etc can have a local effect on temperatures, adding to the ‘chaos’ in the atmosphere. Thanks for bringing this neat phenomenon up!
On a different but hey-that’s-cool topic (get it? ‘hay’ and ‘cool’), here’s a neat link showing the solar eclipse shadow from last week:
http://cimss.ssec.wisc.edu/goes/blog/archives/3020
We were inundated with mosquitos out there yesterday evening, as Don mentioned during his 11pm forecast. I was outside for ~10 minutes at 8pm trying to water some potted tomato plants, at one point was swatting mosquitos every 5-10 seconds. Walked away with 7 or 8 bites even after squashing dozens of them. Going to spray all the wet areas of my yard this afternoon to put the damper on them…
Thanks again for the great stuff, z. I don’t know what that “is awaiting moderation” is all about; first I’ve heard of it–sorry for the inconvenience.
I remember quite a few years back reading an excellent paper in the Bulletin of the AMS on extraordinary dewpoints found in Iowa cornfields during periods of peak evapotranspiration, and how this moisture likely enhanced convection in the region.
The CPC periodically notes in their prognostic discussions the soil moisture z has discussed here, and this element has almost certainly robbed parts of the NE of a few extra degrees on numerous occasions this year.
The NCEP 500mb ensemble mean is definitely showing a relaxation of the NE trough by next weekend, for at least 3 days, with a hint of weak redevelopment of the trough toward days 15-16. If this trend holds, it may not qualify as a full bore pattern change, but it would be a significantly more seasonable period.
Man, What is the weather.com Buffalo page talking about then? They are forecasting by next Tues thru next w/end (and I know it’s all garbage after 48-72 hours) and have been for a few days now, us getting rather cool around these parts. Any reason for the discord?
There isn’t any real discord, except for next weekend–which is speculative at this point. I reported a trend, not a forecast. As I’ve said over and over, weather.com’s extended outlook is virtually all computer driven. Personally, I never–and I mean never–look at it, and the same goes for AccuWx’s silly 15 day outlook.
I know, and at least sometimes I try to guage your forecasts against other outlets, and quite frankly it’s not fair! You are always the most reliable.
I didn’t say what I said to try to get myself a pat on the back. It’s just that the NWS, my colleagues, and folks like Andy and Aaron are not playing on a level playing field when compared to mainly computer driven forecasts. TWC has some great people behind the scenes, but they don’t have the time to “massage” the forecast product very much. We are not at a point where operational meteorologists are close to becoming obsolete (fortunately!). In other words, it’s apples and oranges you’re talking about. And there’s a good reason we operational mets generally don’t venture beyond a 7 day forecast–that’s because skill scores are pretty awful beyond that time frame.
I had always thought TWC nabbed their local forecasts from the NWS, with some sort of computer-aided extrapolation going out to 10 days (which I essentially ignore because I know it’s worthless).
Changing gears, does the precip. outlook for Sunday bring more rain and t-storms up through the Niagara region? Or will things once again set up well to the southeast?
No, years ago, they used the superior NWS forecast, and didn’t go out 10 days. Now, it’s their own model-based product.
The precip for Sunday does not look very impressive in any case–there may be just a bit more to the S & E, but the Niag Frontier should get some as well, with hints of clearing later in the day.
There are early hints that the slowing of a sharp cold front on Tuesday might raise the spectre of severe weather, with quite a bit of prefrontal heating and decent jet dynamics developing in the PM–IF that timing were to hold.
The 18z GFS takes us out of the one-day-dry, one-day-wet pattern after Tuesday for Wed-Fri next week, with noticeable cooling behind that Tuesday front for a few days.
Yeah! Noticeable cooling!
Any updates Don?
Gotta admit, I wouldn’t mind having Mike or Lindsey chime in from time to time. Blog seems to be on hold over the w/ends unless there is something to talk about. Speaking of which, if I may give a bit o’ constructive criticism its that the weather line is not updated enough during periods through the the day during the w/end. Is this something you do only Don?
Devin, I’m off. I’ll probably check in from time to time during the week, but not on as regular a basis.
Enjoy your vacation Don!
This will make somebody happy, just not me.
http://www.cpc.noaa.gov/products/predictions/814day/
Canada’s all white – must be calling for snow!!
Odd that we’re given an “above-normal” temp outlook over the next 6-14 days by the CPC. Most, if not all, of the local weather forecasts have us in the mid-70s for the majority of this week, with rain/t-storms forecasted on Tuesday, including additional t-storms/rain forecasted into next week (I know, a bit too far off). Wondering if the CPC will revise this outlook within the next few days.
Chris,
This week is not in the same time period as the 6-14 day time frame.
The CPC outlooks are automated over the weekend, and are updated daily in the afternoon on Mon-Friday.
For any fall color enthusiasts out there. There are a number of trees changing color along the 219 between Buffalo and Springville. Most likely, these trees are changing due to environmental stress and not responses to seasonal cues, but they are kicking off the fall color season none the less.
Uh-oh! Don’s on vacation… that means severe weather is coming!!! lol!
Have a RELAXING vacation, Don!!!!
I SWEAR there is a correlation between Don on vacation and severe weather!
Thinksnow -
I am suspicious of Don not only accurately forecasting the weather…but also controlling it as well!!
Don out on vacation = high probability hail and/or tornadoes in WNY. Don always has a few tricks up his sleeve…
You better hope its a mild system on Tuesday, Don or we wont let you go on vacation anymore!!!
Is it just me or does the lead weather guy at Ch. 2 also always seem to go on vacation the same time Don does????
Hahaha! Maybe that Facebook war got out of hand – Don put “Channel 2 guy” in the hospital, and left town until things blow over!
I’m kidding, of course. Where’s my Ritalin?