More On Severe Weather

There were nearly 400 reports of severe weather yesterday in the Ohio and Tennessee River Valleys as a squall line of severe thunderstorms passed through.



There were dozens of reports of tree and roof damage reported throughout the region.

CoCoRaHS observer Michael from Westmoreland, Tennessee lost a pear tree to the storm. Here is a link to his blog with a picture.

The CoCoRaHS observer near Scottsville, Kentucky lost part of their greenhouse roof!

Many of the comments mention winds in excess of tropical storm, and in some cases, hurricane strength.

Many also mention the rain measurements may not be accurate due to the winds blowing the rain horizontally at times.

So let's quickly talk about severe weather and what criteria must be met to classify a storm as "severe".

The National Weather Service has three criteria for a storm to be severe, and a warning will be issued when one or more have been met.

Hail 3/4" in diameter or greater (dime size approx.)

Winds greater than or equal to 58 MPH

Producing a tornado

It looks like the weather will be a little more on the quiet side (in terms of widespread organized severe weather) for the next few days.

In addition to the line of severe thunderstorms yesterday, it was just down-right windy across a large section of the eastern US.

Look at the surface observations from mid-afternoon. Windy!!



By the way, if you are not familiar with how to read a wind barb, here is a great link. Click here.

Weather Making Headlines, Both Local & Abroad

Wow Tuesday turned out to be a deadly day in the Sooner state.

Sadly, a large tornado claimed several lives in Lone Grove, which is just west of Ardmore. (between Oklahoma City and Dallas on I-35)

Here is a link to a local television station in Oklahoma City with more inforamtion, pictures, and video.

Click here.

On the above web site you will also see an amazing video of a tornado forming live on camera. You can look for it or simply Click here.

Around the globe, high winds have been battering France and England. Both major airports in Paris had to be closed for the first time in 34 years due to the dangerous flying conditions.

Click here to read more.

And to our north in western Canada, unusually warm weather created the right conditions for a major ice storm that halted travel and caused widespread damage to trees and power lines.

Click here to read more.



More severe weather is expected today -- with a large area of the eastern USA potentially under the gun -- outlined in green on the above map.

As of this blog posting, tornado watches have already been issued for much of the central Ohio and Tennessee River valleys.

Let's keep our fingers crossed that there are no more deadly storms.

Regardless of storms, much of this area will see extremely high winds today. Almost all of Indiana, Ohio, Kentucky, West Virginia and surrounding locations are under a high wind warning.

And how is this for advanced notice -- the National Oceanic & Atmospheric Administration (NOAA) is already alerting the residents of the Red River Valley, which sits between North Dakota and Minnesota, of potential flooding this spring.

It has been a few years since they saw a major flood.

Several conditions are making for the potential flood setup, and you can read more about them in the article linked here.

More Severe Weather, A Chilly History Lesson

Wow it just seems too early to already be seeing maps like the one below, with a moderate risk for a severe weather outbreak.



I will have to call my family and tell them to keep an eye on the sky.

You expect to see maps like the one above in late March and especially April and May, but not before mid-February.

It makes me think about a tornado outbreak on March 1, 1997 -- when I was still living in Little Rock.

I went to work at JCPenney that morning and it was so muggy and warm I had the air conditioner on in the car.

That afternoon, the "loaded gun" sounded and storms fired. There were over a dozen tornadoes, with 2 very long track twisters. One was on the ground 67 miles and the other 75 miles. Several people lost their lives that day in Arkansas.

My aunt's town (Arkadelphia) was leveled by a twister that touched down and moved all the way into the southwest side of Little Rock.

She now has a safe room in her house, which is the master closet. It is built out of concrete blocks and has a steel door.

I was working the switchboard at JCPenney that day and when I took a phone call from the store manager's husband saying plywood and other debris was falling out of the sky in Cabot, which was 30 miles northeast of us -- and about 50 miles northeast of the tornado's position -- I got really scared.

We sought shelter in the mall because the storm was heading straight for us. We locked all the doors and customers had to choose to either stay and ride it out or leave.

Thankfully, the twister lifted for a brief period as it passed over the mall. But we didn't miss out on the wind and rain.

After the storm passed, all the cars in the parking lot were covered with tree leaves and small branches.

It was crazy!

Click here and you can see a complete recap of that day in Arkansas. The tornado that took out my aunt's town and nearly hit the mall I worked at was Track #1 on the map with storm tracks.

On a colder note, on this date back in 1899 the lower 48 states were in the DEEP FREEZE! Much of the center of the nation fell to 30 below or lower. Single digit temps, ice and snow made it all the way to the Gulf Coast.

Between the 11-13th, nearly every location in Arkansas was below zero to show you how cold it was that month.

Ice flows on the Mississippi River reach New Orleans on Feb. 17, unheard of in that part of the world.

The ice flowed into the Gulf of Mexico on the 19th.

Snow fell in Jacksonville, Florida and sub-freezing temps moved all the way south into Miami.

To this date, many locations, especially in the south, still have February 1899 record lows that stand and have yet to be broken.

Here is a great article written about the cold wave, complete with some hand drawn maps of just how much territory the frigid temps covered. Click here.

First Thunderstorms of 2009

The southern plains saw their first outbreak of severe thunderstorms on Sunday. My good friend and storm chaser, Tony Laubach, logged over 1,200 miles and 16 hours in the car chasing with some of his partners.

Click here to visit his web site and see more about the chase.

Here is the set up that spawned the storm event. Now granted this wasn't huge, mostly rain, a lot of wind and a dozen or so reports of large hail.

But still, in particular for the storm chasers, it let's you know that severe weather season is knocking on the door!



As a strong area of low pressure pulled east from the Pacific, it produced very strong winds out ahead of it from the south.

This helped pull up low-level moisture for the storms to feed upon.

You can see just how strong the winds were out of the southeast, feeding into that approaching area of low pressure in the picture below. On this map, wind speed is represented by the barbs on the flag. The more there are, the stronger the winds, such as shown over west Texas.



Now here is an interesting picture for you. It shows isobars, or lines of constant pressure across Texas.

When you have this much of a pressure change over a short distance, you can definitely expect wind.

This is nature's way of balancing out the atmosphere -- by moving air around until the pressure difference subsides.



The Lubbock office of the National Weather Service did a nice write up on Sunday's thunderstorms.

Click here to read it.

Here is a map of the storm reports from eastern New Mexico and west Texas on Sunday.



This morning, as that area of low pressure pushes northeast, there has been a small pocket of severe weather across northeast Kansas and northwest Missouri.



Most of the maps above are from the Storm Prediction Center's web site if you are interested in exploring weather events on your own.

New Poll, Possible Severe Weather This Weekend

The old poll has closed and the winner for our favorite cold weather fix was hot chocolate.

We had 73 voters, and the results were as follows...

Hot Chocolate -- 38%

Soup/Stew -- 23%

Chili -- 21%

Coffee -- 16%

I posted a new poll today.

No surprise that coffee was in last place. I think that is just a fix for many people any day of the week, regardless of the temperature. I know I enjoy a cup in the mornings, esp. the smell as it brews.

Well there is something showing up in the forecasts that we haven't seen in a while, potential severe weather outbreaks.

Can you believe it is already that time of the year?

The battle of air masses will soon start taking place as warm air from the south meets colder air from the north.

Computer models are showing there could be strong to severe storms over the southern plains (Oklahoma and Arkansas in particular) during the first half of the upcoming week.

A new storm system is moving into the western part of the country today. This time the bulk of the energy is hitting California, and that is good --- much of the state is in a drought.

Along with the rain comes cooler temperatures. Las Vegas, for instance, is expecting highs in the 50s and lows in the 40s for the next several days.

Winter East, Spring West --- But For How Long?

Good morning from Poughkeepsie! Upstate New York is nothing but trees (and right now, snow)! It is absolutely beautiful.

It is particularly pretty here along the banks of the ice filled Hudson River.

So in my 2 minutes of looking at the weather, it looks like winter is still gripping the east, all the way to south Florida.

There are numerous freeze warnings in place.

I know the west continues to be warm from talking with friends back in Denver.

However, the long term 6-14 day forecast from the climate prediction center is still, and has been for over a week now, calling for a cool down to below normal temperatures in the west with a warmup to above average in the east.

A complete flip flop from how things are today.

I think that will be good -- balance things out a little.

I need to run -- heading into New York City today and flying home to Denver tonight.

I'll make time to get a normal, more detailed blog posted before the week is over.

Coastal Storm A Dud?

Good morning from Albany, NY where it is currently snowing ever so lightly.

My co-worker and I fell on the ice yesterday in a parking lot of one of our accounts. She fell, I tried to break it and next thing I knew we were both laid out on our backs laughing so hard we couldn't stop.

Luckily no damage to either of us!

There is a coastal storm brewing off the northeast US and it will give a glancing blow to areas from New York to Boston and Cape Cod.

We are on the extreme fringe here in Albany with flurries.

The big picture right now is cold and at times damp in the eastern half of the nation. It's even chilly in Florida!

The west is high and dry.

Sorry for no big weather details or blogs....have to keep a tight schedule on the road.

Have a great day!

Groundhog's Day

Good morning from Syracuse, New York!

There is A LOT of snow on the ground here and they are expecting more this week.

I just saw on the news that Phil the groundhog is predicting 6 more weeks of winter.

The newscaster said it has been 10 years since Phil has actually predicted an early spring.

That is all for now, I will try and blog a little more tomorrow from Albany.

Quick Break From Blog

Hey everyone! I am traveling from Sunday-Wednesday and will most likely not have computer access.

IF I do, I will try and make time to blog at least once.

Meanwhile, the long range outlooks (8-14 days) keep hinting at wetter than normal for much of the country with below normal temps in the west.

Could we be getting into an active weather pattern?

It will be interesting to see the updates as we head into the next week.

Snow To Water Ratios

WxWatcher asked a great question about snow water ratios the other day.

The standard that most people learn in a science class is 10 to 1, written was 10:1.

This means every ten inches of snow typically melts to about an inch of water. It is ok to use that standard for classroom purposes, and I think in real life more times than not that comes out to be true for many.

BUT -- location, time of the year, temperature, the source of water and the upper air connection to that source of water -- all these factors play a big role in what the ratio will actually be.

OSNW3, your link to the chart was great. Click here for the chart. I have never seen a chart like that but it certainly gives a guideline.

And as we all know, there are ALWAYS exceptions to every rule when it comes to weather because there are just so many variables to consider.

Ricker, you are right --- temperature plays a large role in the ratio. It also varies by location and the time of the year.

Here in Colorado, the early and late season snows are closer to the 10:1 range, while the mid-winter snows are 15:1 or more. The high mountains can see 20:1 or 25:1, meaning 25" of snow for just 1 inch of water. Now that is what you call powder!!

In March 2003, Colorado had a very wet snow that ended a drought and broke numerous records. In my part of southeast metro Denver, I recorded over 40" of snow but it never piled up more than 28" on the ground because it was so full of water and so heavy, it just kept compacting.

It also had a blue tint to it and the weight of the snow literally "squeezed" the water out of the snow below it. The ratio was something like 6 to 8 inches of snow for every 1 inch of water. Just crazy -- particularly for this part of the country!

One might not be shocked to see that ratio near a coast, but we are 1,000 miles away from the nearest major source of water -- an ocean. That pipeline of moisture slammed into here as if it were coming straight out of a fire hose that stretched all the way to the Gulf of Mexico.

So the larger your ratio, meaning 15, 20 or 25 inches to every inch of water, the colder it likely was during the snow. And the opposite it true --- heavy, wet snowfalls usually come with more mild temps, holding in the lower to mid 30s.

Super Soaker For Some, Stuck In Ice For Others

Wow did you see the maps today, esp. in the Ohio River Valley?

There were several 2-4 inch rainfall reports from north-central Tennessee in particular, in the Nashville vicinity.

The CoCoRaHS network is in place across Kentucky and Missouri -- but there is a big gap in data over southeast Missouri and southwest Kentucky today -- likely due to power outages from the ice storm and in some counties a lack of stations.

It will be nice when Arkansas comes online later this spring -- that is a HUGE gap currently on the maps and I know from growing up there that the precipitation patterns are quite interesting.

Based off reading through some of your comments, in particular from Tennessee once again, sounds like some of you experienced rain to sleet and snow.

Just a reminder to have your gauge ready to switch over to winter precip mode in those types of weather situations. (i.e. take the inner tube and funnel lid off and just let the overflow can sit outside and catch all the precip)

A severe ice storm has struck from eastern Oklahoma, across northern Arkansas and southern Missouri, and into portions of western Tennessee and Kentucky.

In northern Arkansas, entire cities and towns are shut down and essentially stuck with widespread damage from downed trees, limbs and power lines.

If you have never been in an ice storm where 1 or more inches of ice accumulate, it is probably one of the most miserable feelings ever. At least with snow you can try and get around, but with freezing rain -- in that quantity -- you become a prisoner to Mother Nature.

And when the power goes out and you are left with nothing but the sound of tree limbs and branches snapping, it's brings an unsettled feeling, especially at night.

Hopefully that part of the world will warm up and melt soon and life can get back to normal -- although it could be several days to restore power, esp. in the rural areas of the Ozarks.

FOG & PRECIP

Someone left me a comment asking one more time for clarification.

Precipitation caused by fog, be it freezing fog or not, DOES count as precipitation.

If possible, leave a comment describing what you observed.

When you have clear skies (keyword clear) and wake up to either frost or dew, this is NOT precipitation.

But it is still worth making a note in your comments if you are so inclined because some CoCoRaHS data users may either have a use for this info or find it interesting.

Winter's Grip & Spring's Tease

Winter is gripping the eastern 2/3 of the nation today.

Wow, there are a slew of watches, warnings and advisories for snow, sleet and freezing rain today -- stretching all the way from the hills around San Antonio, TX through Dallas, Little Rock, Memphis, Cincinatti and right up into New York and Boston. Check out the map below!



Many schools are closed today along the southern end of the wintry weather, as you can imagine, since they aren't used to the wintry weather.

And much of the southern extend is getting ice which when accumulations reach a half inch to inch, it all but shuts down life as we know it until things thaw and melt. Growing up in Arkansas, I've been through many ice storms.

The polls have closed on my last question -- Are we seeing more extreme weather? More than half of the 92 votes said no.

No, I recall crazy weather as a kid -- 34%

No, it's just unpredictable Mother Nature -- 31%

Yes, definitely in my area -- 22%

Yes, but not where I live -- 10%

I have posted a new web poll so check it out.

NOAA has released their 2008 temperature summary for the United States. Overall, the year was near average but December was below average.

Click here to read more.

Meanwhile, spring is teasing the southwest US this week with highs in the 70s to lower 80s expected around Los Angeles and Phoenix by the end of the week.

And a few days ago someone had posted a link to temperatures for the Northwest USA, asking what all the acronyms meant and which one CoCoRaHS fell under?

RAWS means remote automated weather station. SNOTEL are automated weather stations in the mountainous regions of the west. DOT are department of transportation weather stations. Just to name a few...

I would assume CoCoRaHS falls under MISC (if they are using our data that is)

Winter Gripping Many, Stormy Weather Hits Europe

It's c-c-c-cold for most of the country along and east of the Rocky Mountains.

Wintry precipitation is impacting travel from Denver to Little Rock and eventually it will spread into the northeast.

Portions of northern Arkansas and southern Missouri may be trapped by this time tomorrow as over an inch of freezing rain is possible.

If that happens, there will be a lot of damage from fallen trees and power lines.

Looking for warm and dry weather? Head to Arizona and southern California.

Long-term forecast models show a reverse in the trend we have been seeing of late, with the potential for warmer and drier weather to take over the eastern part of the nation as we head into February with cooler, wet weather for the west coast.

If that happened, I think we'd all be okay with it as the east would like to warm up and in some cases dry out -- and the west coast would like to see a little bit of their winter precipitation. (I am talking places like northern and central California, not the coasts of Oregon and Washington which were drenched in recent weeks)

Take all this information with a grain of salt. About the only thing in the long-term forecast that I really bite off on is the models show another round of bitterly cold air taking over Alaska -- similar to the air mass that was in place late December and early February.

Now that I believe.

It has been very stormy in Europe over the past few days. Flooding rains have hit parts of the United Kingdom, and high winds across northern Spain and southern France have caused severe damage, cut power to over a million households and claimed over a dozen lives.

Click here to read more.

CoCoRaHS Affords Opportunity To Teach US Climate Like Never Before

It continues to be cool for much of the country with a few pockets of unsettled weather -- the cold is the main story, however, this weekend.

Let me take a minute here and get caught up on all your comments.

Fanghopper asked if the clippers have been more frequent than normal this year?

For those not in the Great Lakes, upper midwest or northeast -- clipper systems are weak cold fronts that move out of Canada and "clip" this region of the US.

They typically bring a reinforcing shot of cold air and squeeze out any available moisture in the form of a light, fluffy snow.

It does seem like there have been TONS of clippers this year but I just don't know enough about the climatology for your part of the country to know if this is above normal or not.

I'd venture to say it may be since the weather pattern this winter has been very persistent. (i.e. here in Denver we've been high and dry just about as long as you have been being hit with clipper after clipper)

John I sent a note up to CoCoRaHS central about your suggestion for expanding the training info.

I know there has been a lot of comments and debate over fog/freezing fog and if it is precipitation or not.

I misreported in a previous entry but for CoCoRaHS purposes, we ARE counting anything measured in your gauge from fog and freezing fog as precipitation. If possible, also make a comment about the fog just so users of the data know where the precipitation came from -- fog instead of passing showers for example.

I think now that CoCoRaHS is growing so large and is in so many states, with more than 5,000 pair of eyes making daily reports and comments each day about what is happening -- we are going to see more and more questions like this come up.

We are logging more data than any doppler radar scanning the skies could ever hope to record.

If you think about it, and if you look at a national plot of "first order" or "main" weather stations, talking about the main anchor locations for your state, there aren't that many for a country the size of the US.

It is a great representation BUT there are also many many gaps.

And when you add in all the secondary locations, such as on mountain passes or in smaller, remote towns -- which try to fill in these gaps -- there still aren't near as many as we would like to really study and learn the weather patterns of our country.

And here we have over 5,000 humans going out and making daily weather notes about the climate, observing things in some areas that quite possibly may have never been previously recorded -- certainly not to this extent.

I want to take this freezing fog issue for example -- it is not a new weather phenomena by any means.

But in the past, it was probably only observed at one or two locations during a widespread event across northeast Washington -- let's say both Spokane and Colville reported freezing fog and each station picked up 0.05" of moisture a day over a 5 day period -- they are 70 miles apart.

Big deal -- no one probably ever really thought that much about it before. It's fog and two places received a minimal amount of moisture. A total of a quarter-inch over a 5-day window.

Freezing fog is a very important issue for the transportation industry, but do we think of it as a valuable source of water?

Probably not.

Now with CoCoRaHS -- through the detailed reports filed by you the observer -- just pretend we saw a stagnant weather pattern set up with 5 days of freezing fog over a 100 square mile region of northeast Washington.

And pretend that in that 100 square mile region we have at least a dozen observers, but ideally many more.

When before, precipitation from fog in that same area was picked up only by just the 2 main reporting stations mentioned above, Spokane and Colville -- now we see at least a dozen reports over a several county area due to you.

It may spark all kinds of new studies and interest for someone like a graduate student to look at the question, can and does fog bring beneficial moisture to a region when it is widespread and persists over several days?

A quarter inch of moisture from a 5-day fog over a 100 square mile area would be HUGE if you look at it in terms of how many gallons of water it actually measured out to be!

Kind of a corney example and far-fetched possibly, but I did that intentionally just to show one of hundreds of examples of how 5,000 people taking simple precipitation data with a few comments makes a difference, and brings a meaning and a purpose you may not have thought about.

By the way, if that 100 square mile area did ever see a fairly uniform quarter-inch of moisture from freezing fog over a 5-day window, that would be equivalent to over 400 million gallons of water for the landscape to absorb.

A water company would LOVE to know that kind of data -- and I think it's pretty interesting to pretend that a prolonged fog event could deposit that much moisture if my pretend scenario actually did ever take place.

Here is a cool link that will help you see how I calculated the above water statistic.

My dream (and I am sure Nolan and Henry too) is to have enough money so we could support deeper employment with CoCoRaHS.

I'd love to sit down each day, read the comments and reports, and put together recaps, graphs, etc --- a climate "atlas" if you will -- of what we are seeing, observing, and learning about the climate of the United States.

Unfortunately I have too much debt like the rest of you and work 2 jobs to survive -- I do good to write this blog some days -- but I think one day we'll get there.

In the meantime, keep making your daily reports because every last bit of it is being archived and will be used down the road to learn more and more about the weather that impacts our daily lives.

And thank you for voting in the blog poll this week -- nearly 100 votes cast so far!!!

P.S. If there is something you are observing for your region that is of interest to you and you are one that would be inclined to study and analyze -- feel free to do so. I will be happy to help guide you as I am sure Nolan would be too.

It may be a section of your area that always seems to be wetter or drier. Maybe it's the precipitation from fog! Maybe something that needs a long period of data, perhaps up to 2 or 3 years?

The more we learn and document weather and weather patterns that become apparent thanks to CoCoRaHS and our growing network, the better we can demonstrate the value of our organization to potential sponsors.

Correction On Fog & Precipitation

I talked with Nolan today and I stand corrected on the freezing fog comment in my last blog.

Freezing fog -- or any moisture deposition from fog -- DOES COUNT as precipitation since it is deposition from cloud water.

It just happens to be a cloud at or near ground level instead of thousands of feet in the air.

Frost and Dew, however, formed on clear nights, does NOT count as precipitation.

See -- all your comments and blog interaction has taught me something new today!!