Blog Questions

An observer left the following questions yesterday so I will try to answer them as best I can.

Q. How many Traces of rain = an inch of rain?

A. Subjective so no answer. What I call a trace of rain may differ from what you call. Neither are actually measured in the gauge. Meaning the first line on the gauge is 0.01 inches. There isn't a "trace" line.

If I am out doing yardwork and a shower or strom approaches but barely misses me, and I feel about a dozen drops of rain and actually see the drop mark left on the sidewalk -- I would definitely call it a trace.

You might want to see the entire sidewalk and other surfaces completely wet before calling it a trace. Or since it "traced" so much, but still didn't quite measure in the gauge, you might go ahead and call that big trace a 1 hundredth of rain.

Does that make any sense?

So since a trace is not really measured, but interpreted, who knows how many equal an inch.

Personally, if that question were on an exam I would answer zero, then give a verbal explanation like I did above.

Q. Concerning hurricane Ike, are hurricane hunter planes allowed by Cuba, to over fly their country?

I found online that NOAA is the only federal agency with hurricane tracking capabilities that is authorized by Cuba to fly in its airspace.

Ike's Cuban Wrath

Hurricane Ike has given Cuba about the worst blow a storm could give, literally hammering the entire island nation coast to coast with high winds and surf and very heavy rain.

The good news for the US and the main population centers of the Gulf Coast is that it seems like with every model run the westerly storm track gets pushed further and further south.

Current thinking is the storm will impact extreme south Texas, somewhere from Brownsville to Corpus Christi, which is not such good news for these folks.

It's just something we'll have to watch.

In response to my blog question Monday, here is one reply from Missouri.

"Here in Mid-Missouri, there are big, thick, black wooly worms. Lots of folks think that means a hard winter ahead. We had almost 30" at this station last year, so it would be something to beat that! "

Could the black, wooly worms be a tell-tale sign from nature of the potential winter months ahead?

Any more things you all are seeing out there?

Sorry for the short blogs this week. My boss is in town and we are doing a lot of traveling.

What Are Your Cold Season Predictions?

Good morning from a chilly Denver -- it is hovering just about 40 degrees.

There was even a few reports of snowflakes in the southern burbs this morning.

So what are your predictions for the upcoming fall and winter season? I saw one report not too long ago that the Farmers Almanac, which claims an 80-85% forecasting success rate, saying that all but the extreme west and southeast coasts are in for a cold season.

The almanac predicts above-normal snowfall for the Great Lakes and Midwest, especially during January and February, and above-normal precipitation for the Southwest in December and for the Southeast in January and February.

The Northeast and Mid-Atlantic regions should be unusually wet or snowy in February according to the almanac.

The Climate Prediction Center is showing warmer than normal temperatures as we head into the fall season.

So what are your thoughts? Are you seeing any natural signs of a hard winter where you live?

(i.e. the animals are storing up earlier than normal)

I know as a kid in Arkansas, I was always told that thick foliage in the warm season was a sign that a long, cold winter lie ahead.

I don't know that there is any truth to that but that is what some believe.

I heard a reference the other day comparing this year's hurricane season to that of 1995.

So I looked up the winter of 1995-1996 and found this article.

If indeed there is a comparison between the two hurricane seasons, will there be one between the winters too?

According to this one example, then maybe the Farmers Almanac will be right?!?

Of course the bottom line is all we can do is wait and see -- but I do think it is fun to not only look at climatology (past weather) but also any signs our environment might be showing us, if any at all.

Hanna Bringing Beneficial Rainfall

Hanna has moved on shore in the Carolinas, and the CoCoRaHS maps should be quite colorful today from this region.

It will be neat to follow the progress of the rain shield up the coast this weekend as Hanna moves northeast.

Now our eyes will turn to Ike -- a dangerous hurricane. South Florida is really gonna have a close call with this one, and even potentially a direct hit.

If it doesn't hit the mainland of Florida, it may move over the Keys and then get into the Gulf of Mexico - and could potentially threaten Louisiana and Mississippi yet again.

I was checking out websites and found a great video on WRAL in Raleigh, NC that shows storm surge from a landfalling tropical system.

Click here to watch.

Gustav Soaks Chicago-land

Look at the maps for Thursday -- esp. Illinois and Michigan.

Heavy rain soaked much of this region as the remains of Gustav passed through. It dropped a widespread 3 to 5 inches and in some cases more.

Now eyes turn to our east coast CoCoRaHS states as Hanna moves by this weekend.

Then there is Ike -- a major hurricane that is closing in on giving south Florida either a close call or a direct hit.

If you live in this area, have family and friends there, or are planning travel early next week, keep on top of the latest this weekend.

Right now, if the projected path comes true, it will pass just off the tip of south Florida, impacting the Keys, Miami-Dade County, and surrounding areas.

Tropical Trio Threatens Coast

Wow, Hanna is still with us after spinning over a week between the Bahamas and Hispanola.

Now she is on the move and will impact the weather along the coast of the Carolinas this weekend.

Although a threat, I think the real danger is coming on her heels with Ike. Currently a category 4 storm, Ike will be near the Bahamas in a few days.

The remains of Gustav will drop moderate rains today from the Gulf Coast to Michigan. The CoCoRaHS maps remain busy tracking the footprint of this storm system.

Today's Lesson

So yesterday we teased today's topic -- convection!

This is the transfer of heat by the mass movement of a fluid (such as air and water). This type of heat transfer takes place within gases and liquids because they can move freely and currents can set up within them.

In the atmosphere, convection happens naturally.

Once the sun rises each day, the process begins as some areas of the earth's surface absorb more heat from the sun than others.

As a result, the surface is heating unevenly and you get currents or pockets of rising air. Some of the pockets or currents rise higher than others.

This is called differential surface heating and it is one reason why your airplane flight can be bumpy.

Ever flown into Vegas or Phoenix during the summer with clear skies but horrible turbulance? Differential surface heating and thermals in the desert are part of the reason for such a rough ride.

The heated air becomes less dense and expands, rising up. Heat is transferred up in this process.

This air expands and spreads out, eventually cooling and then it slowly begins to sink.

The now cooler, heavier air flows toward the surface to replace the rising air. Eventually the cooler air heats and the process starts all over.

This vertical or upward exchange of heat is called convection, and the rising bubbles of warm air are called thermals.

The cycle of rising air, being replaced by the cooled sinking air, only to heat up and rise again is called a thermal cell.

Taste of Fall

A pool of chilly air has been on the move in the west.

The Front Range awoke to morning temps between 40-45 degrees, with Denver at 46 degrees.

It was cooler north of town toward Ft. Collins and Cheyenne.

Some impressive rain totals keep streaming in from the remains of Gustav.

Some storm totals in Louisiana have reached the 10-15 inch range.

Notice the big hole on our map -- Arkansas. They have seen a widespread 3 to 7 inches and it continues to rain.

Hopefully they will be part of our network next year.

All eyes remain on the tropics. Hannah wants to get her act together and become a hurricane once again. Current models take it very near the northeast coast of Florida, turn slightly northeast and then make a landfall near Myrtle Beach, SC.

That is still days away so we will just have to watch it and see what happens.

Currently, the storm is moving north at 2 mph.

Today's Lesson

Conduction is the transfer of heat from molecule to molecule. An example of this would be to hold one end of a straight pin between your fingers and an open flame and you will soon feel the heat of that flame!

Heat flows from warmer to colder regions.

Some materials, such as the metal pin, are good conductors of heat.

Other materials, such as air, are bad conductors of heat.

Air is such a bad conductor of heat that on a clear, calm day -- heat stored in the ground only warms a shallow layer of air immediately above the ground.

Yet the air can carry energy rapidly from one region to another with no problem. So how if it isn't a good conductor?

The answer is convection.

Tune in to tomorrow's blog for more.

1-2-3-4 Punch?

Well, Gustav is now inland and still doing some damage from flooding rains and tornadoes.

I want to show you an example of how your CoCoRaHS data is being used. (this is just one of dozens of potential examples)

The Hydrometeorological Predction Center, which takes over forecasting tropical systems once they are inland and convert to a remnant low pressure, puts out public statements a few times each day. They always include rainfall totals.

Click here to see the most recent statement. Scroll down and look at the rainfall totals. Notice how many are from CoCoRaHS!

Are any of these totals your total? I'd be pretty excited if they were using my data.

Back to the 1-2-3 and maybe even 4-punch.

There are 3 systems potentially to go.

The most imminent is Hannah, formerly a tropical storm, then hurricane, now back to tropical storm.

It should reclaim hurricane status over the next day or so as it begins to move along the eastern coast of Florida.

Locations from Miami to Virginia Beach should keep an eye on this storm.

Behind Hannah comes Ike and Josephine -- both way out in the Atlantic, but both poised to move into the Caribbean and eventually may threaten the US.

If you like following the tropics and have never been to the National Hurricane Center's website, I encourage you to click here and visit now.

We'll get back into the daily weather lesson hopefully tomorrow. I am short on time today.

Tribute To Odie And A Little Tropics Talk

Odie's Obit

Friday was Odie's viewing and Saturday was her funeral. Wow it was really tough to process that she has departed this world.

I have known Odie since about 2002 when I joined CoCoRaHS and started doing student work with the Colorado Climate Center.

One thing I loved about her was she was very passionate about students. In my educational career, I met all kinds of people. Some that you had to earn your way into their life, and others that met you once and immediately connected -- there to help you with whatever it was you needed, with a very positive attitude.

Odie definitely fell into the immediate connection category.

Later after I graduated with my degree and worked at Channel 7 as the weather producer, I cannot tell you how many times she helped me find weather data for something I was working on.

I was fortunate that I got to visit her two times since the middle of July. Each trip to the climate center we got to visit for about 30 minutes.

On my last trip, near the beginning of August, I told Odie she looked like she was losing weight. In her sweet but slightly sarcastic way, she chuckled and said what are your eyes not working?

I laughed back and said no you are losing weight, I can really see it in your face.

Little did I and anybody know, that was probably outward signs of the cancer her body was fighting.

Odie had been tired and having pain in her legs from what people at the funeral told me. She went for tests to see what was wrong on Aug. 21 and was diagnosed with stage 3 ovarian cancer that was spreading to other parts of her body on Aug. 22.

And just after midnight on the 25th, she passed away suddenly and very unexpectedly.

One of her dear friends spoke at the funeral. She said as hard as it is to think she is gone, the reality she would have faced over the weeks to come with extensive surgery and chemo, the outcome likely would have been the same.

Although no one wants her gone, at least she didn't suffer this way.

I think that was very brave of Odie's friend to say -- and I completely agree.

Please say extra prayers and send warm thoughts to all her friends, family and her husband, Jim.

Also keep your thoughts going Nolan's way too. Next week will be hard for him, returning to the office where he and Odie worked side by side for 30 years.

I am not sure if he is ready for a ton of emails and phone calls. Besides the emotional aspect of returning to work on Tuesday, it will also be back to business with dozens of phone calls and probably hundreds of emails to return.

If you want to reach out, you might consider a thinking of you card. Here is the address to the climate center.

Nolan Doesken
Colorado Climate Center
Department of Atmospheric Science
1371 General Delivery
Colorado State University
Fort Collins, Colorado 80523-1371

Nolan and the climate center are surrounded by a lot of people willing to pitch in and do anything it takes to get through this tough time.

Tropics Talk

It looks like Hurricane Gustav will make landfall in SE Louisiana on Monday as a strong, major hurricane.

Tropical Storm Hannah, currently being impacted by Gustav, is expected to gain strength and parallel the east Florida coast once Gustav moves inland and weakens into a rain producing low pressure.

The SE states (Geogria, N. and S. Carolina) could see impacts from a landfalling Hannah later this week.

There are yet 2 additional disturbances in the far east Atlantic, and they could become the "I" and "J" storms sometime this week.

The hurricane season in the Atlantic Basin peaks around Sept. 10 so this level of activity isn't really all that unusual for this time of year.

Fay Helps S.E. Drought

It isn't over by a long stretch, but it looks like Fay did put a dent into the exceptional drought conditions over the Smoky Mountains.

There was also a vast improvement over Alabama, portions of Ohio and Pennsylvania.

Check out the maps below from 8/26 and 8/19.

Longer blogs will return over the weekend. My schedule has been a little hectic since Wednesday.

The Cup Runeth Over For Some

Look at the US Drought Monitor data from last Tuesday -- in particular, the bullseye over the Smoky Mountains.

I will post the new data once it updates, reflecting moisture from Fay.

The footprint of rainfall from Fay as the remnants push northeast over the mid-Atlantic is amazing.

The drought stricken area is really loving all this moisture.

Look at Tuesday's CoCoRaHS map, then look at this drought map above.

On Tuesday, western N. Carolina saw the bullseye of precipitation. The observer near Taylorsville said the rain fell so hard it was like a hydro-blaster hitting the roof!

An observer near Weaverville said it was the most rain ever recorded since being a CoCoRaHS volunteer.

I know that day will rank right up there with other memorable moments, such as a first date!! SERIOUSLY!! It is exciting stuff!

A Kannapolis observer said flooded roads and more rain coming -- a real CoCoRaHS day!

Tomorrow's maps will reflect more rain for the region, but the heavy rain core should shift up into Virginia.

WATCHING THE TROPICS

Tropical Storm Gustav should once again achieve hurricane status today and could grow rapidly once it hits the straits between Jamaica and Cuba.

Forecasts take it into the Gulf of Mexico as a major hurricane and aim it somewhere between Houston and Mobile.

We all really need to keep an eye on this one!

Today's Lesson

Yesterday we talked about latent heat. It is important because it is a source for atmospheric energy.

To recap, energy leaves water through evaporation and is "hidden" or trapped in water vapor molecules.

These molecules get swept away by winds and become airborne in the atmosphere.

As the water vapor rises to high altitudes where the air is colder, the vapor changes into liquid and ice cloud particles.

During these processes, a ton of heat energy is released into the environment, serving as the fuel for the weather we see here on the ground. (i.e. hurricanes, thunderstorms, etc.)

Now you see the importance of the condensation-transportation-evaporation mechanism for the relocation of heat energy.

Will Fay Be Drought Buster?

Check out the CoCoRaHS national map today. It couldn't be prettier!

Widespread rain fell across the eastern half of Tennessee, northern Georgia and Alabama, and the western Carolinas.

This is the drought-stricken area that although has seen some rain in recent weeks -- has not been blessed with anything widespread and significant for quite some time.

The moisture is all thanks to the remnants of Fay, still lingering over the deep south.

All eyes are now turning the Gustav -- a rapidly growing hurricane in the Caribbean.

The forecast track is being influenced by a weather feature over the Atlantic. As this moves east, high pressure building over the Bahamas is expected to ultimately steer the storm further west than previously expected.

Gustav will likely make it into the Gulf of Mexico but where, when and on what path remains to be seen.

This is definitely one to keep your eye on over the next few days.

Today's Lesson

We talked in an earlier blog about water vapor (which is a gas) and how it changes into two states -- liquid (rain) or solids (ice).

When it changes state, or phases, heat energy is requierd.

This heat energy is called latent heat.

To understand this concept, let's pretend we are looking at a water drop under a microscope.

On the surface of the water drop, molecules are constantly escaping. This is called evaporation.

The molecules that are escaping are the ones that are most energetic, or the fastest moving molecules.

As they leave, the average motion of the molecules left behind in the water drop decrease.

Since temperature is a measure of average molecular motion, the slower motion of the water drop's molecules suggest a lower water temperature -- although the actual temperature of the drop may or may not change even though evaporation is happening.

What this tells us is that evaporation is a cooling process.

Remember we learned that energy is neither created nor destroyed.

So the energy that left the water drop we were looking at under the microscope can be thought of as being carried away and "locked up" in the newly formed water vapor molecule.

This energy is now stored, or hidden, because the temperature of the the water drop changing from liquid to vapor is still the same.

The heat energy will reappear as sensible heat (heat we can feel and measure) when the vapor condenses back into liquid water -- this teaches us that condensation is therefore a warming process.

Condensation is the opposite of evaporation.

So here are some new terms for you.

The heat energy released when water vapor condenses to form liquid droplets is called latent heat of condensation.

And the heat energy used to change liquid into water vapor is called latent heat of evaporation.

Fay Rains To Date

Sorry for not posting over the weekend -- something caused my allergies to flare up and I was miserable! My left eye was nearly swollen shut.

Much better today!

A blog viewer asked me about the specific heat of water from the last blog entry -- wondering if that applies to all forms of water. (i.e. solid, liquid and gas)

The answer is no, it only applies to the liquid form of water. Specific heat capacity is about 50% less for frozen water (ice) and it is slightly less for water as a gas (steam) at constant pressure.

Specific Heat of Substances given in Calories per Gram times °C.

Water (pure liquid state) -- 1.00

Wet Mud -- 0.60

Ice (0°C) -- 0.50

Steam -- 0.48

Sandy Clay -- 0.33

Dry Air (at sea level) -- 0.24

Quartz Sand and Granite -- 0.19

I wanted to share some rain totals from Fay -- compiled from various sources by the Hydrometeorological Prediction Center.

...LOUISIANA...

BATON ROUGE 2.80
BOOTHVILLE 1.92
NEW ORLEANS (MSY) 1.46
SALT POINT 1.31
SLIDELL 1.15
NEW IBERIA 1.07
LAFAYETTE 0.76

...MISSISSIPPI...

STARKVILLE 5.3 S 2.88
NATCHEZ/HARDY 2.72
COLUMBUS AFB 2.47
MERIDIAN/KEY FIELD 2.45
TUPELO 2.20
MERIDIAN NAS/MCCAIN 1.96
JACKSON 1.94
VICKSBURG 1.75
MCCOMB/LEWIS FIELD 1.85
GREENWOOD 1.10
HATTIESBURG 1.01
PASCAGOULA 0.79
BILOXI 0.23
GULFPORT 0.17

...ALABAMA...

CAMDEN 1.0 NNE 6.55
EUFAULA 1.0 SSE 6.26
WETUMPKA 5.0 SE 6.14
TROY 5.65
OZARK 5.42
DOTHAN 4.38
AUBURN 4.05
MONTGOMERY 3.58
BIRMINGHAM 3.31
ANNISTON 2.84
TUSCALOOSA 2.31
EVERGREEN 1.81
MOBILE 1.41

...GEORGIA...

THOMASVILLE 2.8 E 17.43
COOLIDGE 3.2 SSW 12.03
MOULTRIE 6.2 SW 9.45
VALDOSTA 8.31
LAKE PARK 2.8 W 7.11
ALBANY 4.64
COLUMBUS 4.29
ALMA 4.24
SAVANNAH 3.16
BRUNSWICK 2.88
MACON 2.26
PEACHTREE CITY 1.48

...SOUTH CAROLINA...

BEAUFORT 5.84
MEGGETT 1.8 W 4.97
FOLLY BEACH 2.5 SW 3.96
CHARLESTON 2.72

...FLORIDA...

MELBOURNE BEACH 25.28
COCOA BEACH 24.38
CAPE CANAVERAL 22.83
DELTONA 22.69
SATELLITE BEACH 22.40
PALM SHORES 1.4 W 21.44
PALM BAY 1.0 NE 21.00
ORANGE CITY 19.81
HILLIARD 5.4 NW 19.70
SANFORD 15.70
TALLAHASSEE (TLH) 11.93
FORT PIERCE 11.58
JACKSONVILLE 11.70
VERO BEACH 11.34
CROSS CITY 9.97
DAYTONA BEACH 8.82
WEST PALM BEACH 7.32
ORLANDO 7.26
FORT MYERS 6.85
MARATHON 6.80
MIAMI 6.19
KEY WEST 3.35

Fay Bringing Historical Rain Totals

I tell you, I look at the CoCoRaHS maps each day across Florida and just can't believe what I am seeing!

Click on Florida for today and then look at Volusia County. The view lets you see surrounding counties too.

There are a half-dozen reports between 6.50-11.50 inches and that was as of 6:30am MDT this morning.

Fay is slowly drifting west and may go back over water as it parallels the panhandle over the next 48 hours.

Depending on the exact track, it could make 1 or 2 more landfalls as it follows the panhandle's irregularly shaped coastline.

Elsewhere, most of the country is quiet and seasonal.

Today's Lesson

In weather class, we learn about heat capacity and specific heat.

The heat capacity of a substance is the ratio of the amount of heat energy needed to make a corresponding temperature rise.

The heat capacity of a substance per unit mass is called specific heat.

In other words, specific heat is the amount of heat needed to raise the temperature of one gram of a substance by 1° celsius.

If we heated 1 gram of pure liquid water on a stove, it would take about 1 calorie* of heat to raise the temperature by 1° celsius.

*a calorie is a measure of heat

So therefore, pure water sets the standard for measuring specific heat.

Soil would only need 0.2 calories of heat, so it has a specific heat that is 1/5 less than water.

What this means is that water heats and cools slowly. It has an enormous capacity for storing energy than most other substances.

Why is this important to weather? Because 3/4 of our planet is covered by water.

Boomerang Fay Super Soaker

The circulation around Tropical Storm Fay brought a pipeline of moisture into central Florida off the Atlantic on Tuesday.

Martin County saw a widespread 6-10 inches of rain with 10-15 inches north of there in Brevard County.

One observer in Brevard County saw just under 15 inches of rain! Can't even imagine that -- simply amazing!

More rain is in store as the system slowly shifts to the north and west with time.

Heavy rain also fell around the Oklahoma City metro area on Tuesday with 3" of rain around the suburb of Norman. The rain did cause some flooding there.

Today's Lesson

Have you ever heard of Absolute Zero? This is the lowest temperature possible where there would be no thermal motion from atoms and molecules. (-273°C or -459°F)

At absolute zero we begin a temperature scale called the Kelvin Scale, named after Lord Kelvin, a famous British Scientist.

Since it begins at absolute zero, it contains no negative numbers and makes math calculations easy, therefore it is popular in the science community.

Two other temperature scales are used, the ones most people know, and they are the Fahrenheit and Celsius scales.

The Fahrenheit scale was developed in the 1700s by G. Daniel Fahrenheit, who assigned the number 32 for the point at which water freezes, and 212 for when it boils.

Celsius was later introduced with the number 0 assigned to when water freezes and 100 for when pure water boils at sea level.

Here are some math formulas to convert between these scales.

°C = (5/9)*(°F-32)

K = °C + 273